Prism Flashcards

Question

aerobic gram pos cocci

Answer 1

``` Staph Aureus MRSA Staph Epi MRSE Enterococci VRE Strept pyogenes (A) Strept agalactia (B) Strept Bovis (D) Strept viridans ```

Answer 2

peptostreptococcus

Answer 3

Bacillus anthracis Corynebacterium diphtheriae Listeria Monocytogene

Answer 4

Clostridium perfringens Clostridium difficile Clostridium tetani

Answer 5

``` pseudomonas e coli enterobacter proteus vibrio Y. pestis shigella salmonella klebsiella serratia e. corrodens paturella multicide ``` morganella morganii(?)

Answer 6

bacteroides fragilis

Answer 7

Treponium pallidum | Borrelia burgdorferi

Answer 8

``` xray mri bone scan wbc scan CT PET scan ```

Answer 9

-Soft Tissue: Infection characterized by radiolucent area. One should be able to see a soft tissue deficit if an ulcer is present. It is very important to rule out emphysema (gas in the tissues) with a plain film. Can also appreciate soft tissue edema. -Osseous Tissue: -Early Osteomyelitis (OM) signs: No reliable ones. Rarefaction and periostitis are possible. -Subacute OM signs: Brodie’s abscess (lytic lesion surrounded by sclerotic rim). -Chronic OM: Lysis, Malformation, Involucrum, Cloaca, Sequestra. -Plain film radiographs are 67% specific, 60% sensitive for OM [Termaat, JBJS 2005] -MRI

Answer 10

-Cellulitis: T1: Diffuse and infiltrative decreased signal intensity as inflammation replaces fat. T2 and STIR: Increased signal intensity. -Abscess: T1/T2/STIR: Homogeneous increased signal intensity. -Note that pus/necrotic tissue has a decreased intensity compared to inflammatory fluid. -OM: T1: Decreased signal intensity, cortical lysis and intramedullary changes. -Increased signal intensity in known OM indicates healing as fat infiltrates. T2: Increased signal intensity, cortical lysis, and intramedullary changes. -Rim sign: thin layer of active infection surrounding normal bone. -60% Specificity, 85% sensitivity per Termaat.

Answer 11

-A radio-isotope is injected into the patient and imaged at specific intervals. - Phases: - Immediate Angiogram (1-3sec): Essentially an arteriogram. - Blood Pool (3-5min): Demonstrates blood pooling in capillaries and veins. - Delayed (2-4 hours): Increasingly specific to activity patterns and pathology. - 4th Phase (varying times): Increasingly specific to activity patterns and pathology

Answer 12

- Binds to calcium hydroxyapatite and measures osteoblast/osteoclast activity. - Half-life: 6 hours - Excreted through kidneys which will show homogenous control signal. - Mucomyst 600mg PO q12 day before and of surgery as renal ppx. - Cellulitis: Focal uptake in blood pool; Negative in delayed phase. - OM: Diffuse uptake in blood pool; Hot increased uptake in delayed phases. - 45% Specificity; 86% sensitivity per Termaat

Answer 13

gallium 67 citrate indium 111 oxime technetium 99m HMPAO technetium 99m sulfur colloid marrow scan Combination Sequential Technitium-Gallium scans

Answer 14

- Scan at 4 hours, then at 48-72 hours. Based on half-lives. - Increased specificity for infection if gallium has higher uptake then technetium. - Can use any other combination

Answer 15

- Specific for bone marrow and neutrophil production | - Has shown promise in differentiating OM from Charco

Answer 16

- WBCs isolated from blood samples, tagged and re-injected. Scan at 3 hours. - Tagged molecule is HMPAO (hexamethylpropyleneamine oxime) ->you will get asked this!) - Technically easier with less radiation than indium

Answer 17

- WBCs isolated from blood sample, labeled and re-injected. - Scan at 24 hours. Half life: 67 hours. - Predominantly uptaken by neutrophils, so it demonstrates acute infections better than chronic infections

Answer 18

- Uptake by siderophore complex (direct bacteria) and lactoferrin (protein-released by bacteria) - Scan taken 48-72 hours after injection or done in triphasic manner. - Has longer half-life - 42% Specificity; 80% Sensitivity per Termaat

Answer 19

Radiograph altered by computer to highlight specific “windows”. You can isolate soft tissue or different aspects of bone, for example. - Soft tissue infection: Exact locations and anatomy of abnormal soft tissue density. - OM: Increased density in the marrow. - CT scans can be combined with contrast

Answer 20

- A tracer is injected/inhaled into the patient which releases radioactive positrons. The positrons collide with electrons and produce gamma rays. - >90% Sensitivity and Specificity per Termaat (best in study High sens,spec

Answer 21

neuropathy trauma leading to ulcer impaired wound healing

Answer 22

- 30-50% of diabetics have some form of sensory, motor and/or autonomic neuropathy. - Sorbitol accumulation in Schwann cells leads to hyperosmolarity of the nerve cells in turn leading to swelling and cellular lysis. This leads to decreased nerve signal conduction. Microvascular damage to the nerve (described later) also impairs healing of the damaged nerve. - Sensory Neuropathy - Loss of light touch/protective sensation (anterior spinothalamic tract) - Loss of vibratory/proprioception mechanisms (posterior tract) - Loss of pain/temperature sensation (lateral tracts) - The patient has no warning of current, developing or impending trauma. - Motor Neuropathy - “Intrinsic Minus” foot-type with wasting of the intrinsic muscles and extensor substitution. - Undetected excess plantar pressures develop. - Autonomic Neuropathy - Damage occurs in the sympathetic ganglion - AV shunting occurs with global LE edema not relieved by diuretics or elevation. - Increased skin temperature predisposes to ulceration (Armstrong) - Decreased sweating leads to xerosis and fissuring (portal for infection)

Answer 23

-Abnormal anatomy: extrinsic and intrinsic abnormalities secondary to motor neuropathy and tendon glycosylation. -Decreased joint mobility: secondary to non-enzymatic glycosylation and excess collagen cross-linking of tendons, ligaments, joint capsules (especially at the STJ and the MTPJ). -Equinus: Increased cross-linking of collagen in the Achilles tendon (leads to increased forefoot pressures). -Skin stiffness: secondary to glycosylation of keratin. -Intrinsic skin weakness: trophic changes associated with PVD. -All lead to increased plantar pressures, which is the driving force behind ulceration.

Answer 24

-Can be thought of as increased inflammation, decreased vasculature and decreased catabolism. -Increased Inflammation -The inflammatory phase of the healing process actually lasts longer than necessary. -Inflammation initially not as effective due to decreased leukocyte adhesion and morphologic changes to the macrophages. -Prolongation occurs due to decreased chemotaxis of growth factors and cytokines. -MMPs increase their activity and continue to produce an “inflammatory soup.” -All contribute to a wound “stuck” in the inflammatory phase. -Decreased Vasculature -Macroangiopathy: Atherosclerotic obstructive disease of large vessels due to LDL oxidation. -Microangiopathy: Thickened basement membrane decreases diffusion at capillary level. -Mechanism behind neuropathy, nephropathy and retinopathy -Think of it in terms of a decreased TcPO2 -Endothelial dysfunction: -Decreased nitric oxide (NO) and prostaglandin to promote vasodilation -Decreased smooth muscle cell relaxation to promote vasodilation -AV shunting secondary to autonomic neuropathy -Decreased vasodilation and membrane permeability in response to trauma/damage/inflammation: -Usually regulated by substance P and vasomodulators from damaged cells and nociceptors. -Overall leads to a “sluggish” vasculature with decreased inflow, diffusion, outflow and angiogenesis. -Decreased Catabolism -Decreased collagen synthesis, both in peptide production and post-translational modification -Morphologic changes to keratinocytes -Decreased angiogenesis

Answer 25

``` Skin Superficial Fascia -First Dissection Interval containing superficial neurovascular structures Deep Fascia -Second Dissection Interval containing muscular and deep neurovascular structures Periosteum -Third Dissection Interval Bone ```

Answer 26

- Periostitis: Inflammation of the periosteum - Osteitis: Inflammation of the cortex - Osteomyelitis: Inflammation of the medullary canal - Sequestrum: piece of dead bone floating in pus/inflammation - Involucrum: sheath of bone surrounding pus/inflammation - Cloaca: tract through an involucrum - Brodie’s Abscess (1832): Chronic abscess in bone surrounded by sclerosis - Sclerosing OM of Garre: low grade inflammatory condition

Answer 27

-Acute Osteomyelitis: Systemic clinical signs of infection -Chronic Osteomyelitis: Subacute clinical signs of infection -Contiguous/Direct Extension: spread of infection to bone from exogenous source or adjacent tissue. This can be described as an “outside-in” spread invading the cortex and proceeding to the medullary canal. -Hematogenous Spread: Infective agent reaches medullary canal of bone from the vascular supply. This can be described as an “inside-out” infection invading the medullary canal first and spreading to the cortex. -Vascular Impairment: Decreases the effectiveness of the inflammatory response and Abx delivery.

Answer 28

Weiland: Describes chronic OM as lasting > 6months. | -Schauwecker: Describes chronic OM as lasting > 6 weeks and one failed episode of tx.

Answer 29

- Acute Osteomyelitis - Contiguous/Direct Extension - No PVD - PVD - Hematogenous Spread - No PVD - PVD - Chronic Osteomyelitis - Contiguous/Direct Extension - No PVD - PVD - Hematogenous Spread - No PVD - PVD

Answer 30

-Anatomic Stage Stage 1: Medullary: infection of only the medullary canal Stage 2: Superficial: infection of only the superficial cortex Stage 3: Localized: infection of only the cortex Stage 4: Diffuse: infection of both the cortex and medullary canal -Physiologic Stage A: Normal Host Bs: Compromised Host with systemic risk factors (eg DM) Bl: Compromised Host with local risk factors (eg smoking) C: Treatment worse than the disease - So a smoking DM patient with infection of only the superficial portion of the cortex is: 2Bs - Obviously much more work needs to be done on the topic of osteomyelitis classification.

Answer 31

- Subjective Findings (See Diabetic Infection Work-up) - Objective Findings (Diabetic Infection Work-up) - Probing to bone 89% positive predictive value (Grayson JAMA 1995). - Gold Standard: Bone biopsy. This is ideally performed when the patient has been free of antibiotics for 2 weeks. - Imaging Studies: - Review plain films, MRI, Bone Scans, WBC scans, CT, PET in Diabetic Infection Imaging Sheet. - These all add evidence, but are rarely exclusively diagnostic. - Blood Cultures: Hematogenous OM diagnosed with positive BCx and positive bone scan.

Answer 32

- There is much controversy regarding long-term Abx (PO vs. IV vs. PMMA) vs. Surgical Debridement. - The Cierny-Mader Classification makes some general recommendations: - CM Stage 1: 2 weeks IV + 2-4 weeks PO Abx - CM Stage 2: Surgical Debridement + 2 weeks IV - CM Stage 3&4: Surgical Debridement + 4-6 weeks IV Abx

Answer 33

-Long-term Abx (4-8 weeks) is a conservative option because many people believe you can never cure OM and that it can reactivate at any time for years to come.

Answer 34

- Doxycycline and Ciprofloxacin are reputed to have the best bone penetration. - Keep in mind that most ID docs would never substitute coverage for bone penetration. - Your Abx choices should be culture driven.

Answer 35

- Culture driven | - Access options: IV, PICC, Infusion pump, etc.

Answer 36

- PMMA: polymethylmethacrylate - PMMA is a combination of monomer (liquid) and polymer (powder). - Comes in 20, 40 and 60g packets. - 7% elusion in the first 24 hours with activity noted for 14 days. - Demonstrates exponential release. - Cierny proposes a 1:5 ratio of Abx:PMMA. Another common standard is 4-8g:40-60g. - Increased Abx means increased elution, but decreased bead hardening. - Smaller beads means increased overall surface area and increased elution. - The Abx must be heat-labile - Gentamycin, Tobramycin, Vancomycin, Ticarcillin, Cefazolin, Moxalactam, Cefotaxime

Answer 37

Soft Tissue Only Mild Topical or oral 1-2 weeks up to 4 weeks Moderate Oral 2-4 weeks Severe Initial parenteral, then switch to oral 2-4 weeks

Answer 38

No residual infection Parenteral or oral 2-5 days Residual infected soft tissue Parenteral or oral 2-4 weeks ``` Residual infected (but viable) bone initial parenteral, then switch to oral 4-6 weeks ``` Residual dead bone post-operatively Initial parenteral, then switch to oral >3 months

Answer 39

Neuropathic osteoarthropathy first described by Musgrave in 1703 and named for JM Charcot in 1868

Answer 40

- Trophic centers in the anterior horn of the spinal cord maintain nutrition to joints. - Trauma to these trophic centers leads to increased blood flow and osteoclastic activity. - Evidence for the Neurovascular Theory: - Autonomic neuropathy in DM leads to increased AV shunting, edema and skin temperature. - Boulton: Increased PO2 in venous system of Charcot pts (63mmHg vs. 46mmHg) - Shows increased perfusion in neuropathic diabetics - Edmonds: Increased blood velocity in neuropathic diabetics - Young: Decreased bone density in patients with decreased nerve conduction velocities - Cundy: Decreased bone density in Charcot patients - Gough: Increased osteoclastic activity in Charcot patients

Answer 41

-Repeated trauma from biomechanical stresses during ambulation on an insensate foot. -Evidence for the Neurotraumatic Theory: -Eloesser and Johnson: Trauma is the necessary predisposing factor, and not underlying bone weakness, to create Charcot changes in a neuropathic limb. -Common sense -Two opposing, fighting theories (with two opining blowhards on either side getting red-faced)? Probably a little bit of both.

Answer 42

-First described: Tabes Dorsalis (Charcot 1868) -Most common: DM -3 most common: DM, Syringomyelia (longitudinal cavities lined by dense tissue), and Tabes Dorsalis -C: Myelomeningocele, Spina Bifida, CMT, MS, CP, Syringomyelia, Congenital insensitivity M: DM, Alcoholic neuropathy, Uremia, Pernicous Anemia I: Tabes Dorsalis, Polio, Leprosy, TB N: Tumors in brain, spinal cord, peripheral nerve T: Trauma to brain, spinal cord, peripheral nerve D: Indomethacin, Intra-articular corticosteroids, phenylbutazone

Answer 43

``` OM AVN Inflammatory arthritis PVS septic arthritis CPPD Neoplasm ```

Answer 44

- Presents similar to infection - Red, hot, swollen, deformed foot +/- pain - Neuropathic - Readily available pulses (often described as bounding)

Answer 45

- Atrophic: - With osteopenia, pencil&cup deformities, resorption of bone ends - Without osteophytes, sclerosis, fragmentation, soft tissue debris - Hypertrophic: - With joint space narrowing, fractures, fragmentation, ST debris, periosteal rxn, subluxation - Without osteoporosis - Be aware of both types

Answer 46

- Eichenholtz Classification - Brodsky Classification - Schon Classification

Answer 47

- Acute: - Strict and immediate NWB and immobilization for 12-16 weeks. - Edema control (Jones cast, ACE inhibitors, Diuretics, Posterior splint, Elevation, Ex Fix, etc.) - Education and family support - FXR every 4-6 weeks with relatively few cast changes - Transition: - Transition to WB (CAM walker, CROW, Bracing, MAFO, Shoes, etc.) - Permanent: - Surgical correction of underlying deformity - Consider TAL, Arthrodesis, Wedging osteotomies, Amputation - Adjunctive: - Bone stimulators - Bisphosphonates: -Pamidronate (Aredia): 60-90mg over 24h. 3 doses in 2 weeks. - Alendronate (Fosamax): 5mg PO q24h

Answer 48

- Based on plain film radiographic findings - Originally described Stages 1Æ3, but Stage 0 added later (Yu given credit, but really Schon). - [Yu GV, Hudson JR. Evaluation and treatment of stage 0 Charcot’s neuroarthropathy of the foot and ankle. JAPMA. 2002; 92(4): 210-20.] -Stage 0: High risk pre-Charcot -Radiograph: Unremarkable. Maybe increased ST density, bone flecks or change in foot architecture. -Clinical: Sudden onset of non-pitting edema, erythema, calor, +/- pain, bounding pulses, intrinsic atrophy. -Normal skin temp: 94°F; can increase by 12° -Uptake in all three phases of Tc-99 bone scan - Stage 1: Acute/Developmental - Radiograph: Capsular distention, fragmentation, debris, subluxation - Clinical: Red, hot, swollen foot with joint laxity - Stage 2: Coalescence - Radiograph: Sclerosis, resorption of debris, fusion - Clinical: Subjectively decreased red, hot, swollen - Stage 3: Reconstruction - Radiograph: Decreased sclerosis (with increased vascularity) and remodeling - Clinical: Decreased joint mobility with increased stabilization

Answer 49

- Type 1: Lisfranc joint (27-60% incidence) - Type 2: Chopart’s joint and STJ (30-35% incidence) - Type 3A: Ankle joint (9% incidence) - Type 3B: Posterior calcaneus - Type 4: Multiple combinations of above - Type 5: The forefoot

Answer 50

I: Lisfranc Pattern -AÆC with increasing deformity to medial rockerbottom and ulceration. II: Naviculocunieform Pattern -AÆC with increasing deformity to lateral rockerbottom and ulceration. III: Perinavicular Pattern -AÆC with lateral rockerbottom, Talar AVN and ulceration. IV: Transverse Tarsal Pattern -AÆC with increasing deformity to central rockerbottom and ulceration.

Answer 51

- Please keep in mind that these are not mutually exclusive and both can be present! - These are just general guidelines and many people will vehemently argue about them. - The gold standard is a bone biopsy which would show infection in OM and not in Charcot.

Answer 52

Subjective - OM: Constitutional signs and symptoms of infection, infectious risk factors, history of infection. - Charcot: Uncontrolled DM, history of Charcot, history of recent trauma. Objective - OM: Necrosis, purulent drainage, elevated white count, cultures, positive bone biopsy. - Charcot: Increased joint laxity, non-pitting edema, bounding pulses, rockerbottom deformity, negative bone biopsy.

Answer 53

Imaging -Not enough evidence yet, but some believe that OM is positive on bone scans and WBC scans for greater than 24 hours whereas Charcot neuroarthropathy is only positive during the first 24 hours. -The Tc99 Sulfur Colloid scan would also theoretically be positive for infection, but not for Charcot.

Answer 54

-Increased or Decreased -Radiolucency or Radiodensity -Everything that you see on a radiograph can be described using these terms. So while you may not be able to “see” a fracture, you can describe an area of radiolucency within bone consistent with a fracture. And while you may not be able to “see” an infection, you can describe an area of radiolucency within the soft tissue consistent with emphysema.

Answer 55

MRI: - Increased or Decreased - Signal intensity - Bone scans: - Increased or Decreased - Signal uptake - Ultrasound: - Hyperechoic or Hypoechoic

Answer 56

- Staph Aureus (SA) (if no streaking present) - Strept (with streaking and palpable border) - Usually monomicrobial

Answer 57

Staph Au Strep polymicrobial

Answer 58

Staph Au Strep Enterobacter usually polymicrobial

Answer 59

pseudomonas | poly

Answer 60

- SA -MRSA - Staph epi - Enterococci -VRE - Diptheroids (Corynebacterium) - Enterobacter - Pseudomonas - Extended GNR - Usually polymicrobia

Answer 61

- Resistant Gram positive cocci - Mixed GNR - Anaerobes - Polymicrobia

Answer 62

SA enterobacter pseudomonas

Answer 63

SA enterobacter pseudomonas

Answer 64

gram negatives

Answer 65

salmonella

Answer 66

``` haemophilus actinobacillus cardiobacterium hominis eikenella corrodens kingella kingae ```

Answer 67

vibrio aeromonas hyprophilia mycobacterium

Answer 68

pseudomonas

Answer 69

clostridium

Answer 70

pasteurella multocida

Answer 71

strep virdans | capnocytophaga canimorsus

Answer 72

gram negatives

Answer 73

Staph aureus

Answer 74

clostridium

Answer 75

pseudomonas

Answer 76

- 2ndGeneration PCN -2ndGeneration Quinolones - Synercid - 4thGeneration PCN -Macrolides - Rifampin - 1stGeneration Cephs -Bactrim - 2ndGeneration Cephs - Vancomycin - Carbapenems -Clindamycin - Tetracyclines - Zyvox

Answer 77

- Vancomycin -Synercid - Clindamycin - Bactrim/Rifampin - Zyvox - Cubicin

Answer 78

``` 3/4 PCN 2/3/4 quinolones carbapenems tetracycline aztronam bactrim ```

Answer 79

- Cephalosporins x 3 (Fortaz, Cefobid, Maxipime) - PCN x 2 (Zosyn, Timentin) - Aminoglycosides - Primaxin - Quinolones - Aztreonam - ACRONYM: FAT CIAZ (Fortaz, Aztreonam, Timentin, Cefobid, Imipenin, Aminoglycosides, Zosyn)

Answer 80

``` 4PCN 1/2/3/4 Ceph Aminoglycosides Carbapenems 4Quinolones Clindamycin Flagyl ```

Answer 81

-from Lipsky BA, et al. Diagnosis and Treatment of Diabetic Foot Infections. IDSA Guidelines. CID 2004; 39: 885-910.

Answer 82

- Definition: No purulence, inflammatory manifestations, or systemic manifestations - Empiric Therapy: None

Answer 83

- Definition: - 2+ Manifestations of Infection (purulence, induration or erythema/pain/warmth) - <2cm of erythema - Limited to skin and subcutaneous tissue - No systemic complaints - Empiric Therapy Recommendations: - 2-PCN -Bactrim - Clinda -Augmentin - Keflex -Levo

Answer 84

- Definition: - As above, in a systemically/metabolically stable patient PLUS - >2cm cellulitis OR streaking OR involvement of deep tissue -Empiric Therapy Recommendations: - Bactrim -Invanz - Augmentin -Ceftin + Flagyl - Levo -Timentin - 2-Ceph -Zosyn - 3-Ceph -Levo + Clinda - Daptomycin + Aztreonam -Cipro + Clinda - Zyvox + Aztreonam

Answer 85

- Definition: -Infection as above in a patient with systemic toxicity and metabolic instability - Empiric Therapy Recommendations: - Primaxin - Vanco + Fortaz - Zosyn - Vanco + Fortaz + Flagyl - Cipro + Clinda - Levo + Clinda

Answer 86

- Zyvox - Vanco + Fortaz - Zyvox + Aztreonam - Vanco + Fortaz + Flagyl - Daptomycin - Daptomycin + Aztreonam

Answer 87

Vanco + Aztreonam + Flagyl

Answer 88

1-ceph vanco clinda azithromycin

Answer 89

clindamycine

Answer 90

tetracyclines

Answer 91

aminoglycosides

Answer 92

doxycycline

Answer 93

-PO: Keflex -500mg PO tid or 750mg PO bid Clindamycin -300mg PO qid Zithromycin -500mg PO day 1, 250mg PO days 2-5 -IV: Ancef -1g IV q8 Vancomycin -1g IV q12 Clindamycin -600mg IV q8

Answer 94

-PO: Keflex -500mg PO tid or 750mg PO bid Clindamycin -300mg PO qid ``` -IV: Ancef -1g IV q8 Vancomycin -1g IV q12 Clindamycin -600mg IV q8 3. ```

Answer 95

-IV: Vancomycin -1g IV q12 ``` -PO: Bactrim -1 tablet PO bid Rifampin 300mg +Minocycline -100mg PO bid ```

Answer 96

-PO: Amoxicillin -250-500mg tid Augmentin -875mg bid or 500mg tid (or bid) Zyvox -600mg PO bid -IV: Vancomycin -1g IV q12 Zyvox -600mg IVq12

Answer 97

-PO: Zyvox -600mg PO bid -IV: Zyvox -600mg IV q12 Synercid -7.5mg/kg/hr over 1 hour q12

Answer 98

-PO: Ciprofloxacin -250-750mg PO bid -IV: Ciprofloxacin -400mg IV q12 Fortaz -2g IV q12 Aztreonam -1g IV q8

Answer 99

-PO: Keflex -500mg PO tid or 750mg PO bid Cipro -250-750mg PO bid Levaquin -500mg PO qday Tequin -400mg PO qday -IV: Ancef -1g IV q8 Cipro -400mg IV q12 Levaquin -500mg IV qday Tequin -400mg IV qday

Answer 100

1st Generation: - Pen V: 500mg q6 PO - Pen G: 250,000 units/kg/day IV 2nd Generation: -Dicloxacillin: 250mg q6 PO - Oxacillin: 1-2g q4 IV - Nafcillin: 1-2g q4 IV 3rd Generation: -Amoxicillin: 500mg q8 PO -Ampicillin: 1g q4-6 IV 4th Generation: -Augmentin: 875mg q12 PO - Unasyn: 3g q6 IV - Zosyn: 4.5g q6 IV - Timentin: 3.1g q6 IV

Answer 101

1stGeneration: -Keflex: 500mg q8 PO or 750mg PO bid - Duricef : 2g q24 PO - Ancef: 1g q8 IV 2ndGeneration: -Ceftin: 500mg q12 PO - Zinacef: 1.5g q8 IV - Mefoxin: 1g q6 IV 3rd Generation: -Omnicef: 300mg q12 PO - Vantin: 400mg q12 PO - Rocephin: 1g q24 IV - Fortaz: 1g q8 IV - Cefobid: 2g q12 IV 4th Generation: -Maxipime: 2g q12 IV

Answer 102

2ndGeneration: -Ciprofloxacin: 750mg q12 PO/400mg q12 IV 3rdGeneration: -Levofloxacin: 500mg q24 PO/IV 4thGeneration: -Tequin: 400 q12 PO/IV -Avelox: 400 q24 PO

Answer 103

- Biaxin: 500mg q12 PO - Ketek: 800mg q24 PO - Zithromax: 500 q12 IV/ 500mg PO Day 1; 250 mg PO Day2-5 - Erythromycin 500mg q6 PO

Answer 104

- Invanz: 1g q24 IV - Primaxin: 500mg q8 IV - Merrem 1g q8 IV

Answer 105

- Amikacin: 1500mg/day - Tobramycin: 3-5mg/kg/day - Gentamycin: 3-5mg/kg/day

Answer 106

- Minocycline: 100mg q12 PO/IV - Doxycycline: 100mg q24 PO - Tetracycline: 500mg q6 PO

Answer 107

160/800mg q24 PO

Answer 108

600mg q8 IV | 300 mg q6 PO

Answer 109

600 mg q12 PO/IV

Answer 110

7.5mg/kg q8 IV

Answer 111

500mg q8 PO

Answer 112

``` CC HPI PMH PSH Meds Allergies FH ROS ABCDEs of primary survey Tetanus Status NPO Status ```

Answer 113

-Airway: Three common forms of airway obstruction are cervical spine injury, swollen tongue and facial fracture. -Breathing: Note how this is different than an established airway. Someone can have an airway, but still not be breathing. -Circulation: Assess vascular status in all four extremities. Two large-bore (18-gauge) IV’s should be started immediately if fluid replacement is considered necessary. -Deficits (Neurological): There are two ways to assess this. --AVPU ---Alert, responds to Verbal stimuli, responds to Painful stimuli, or Unresponsive ---Glasgow Coma Scale ----Based upon three criteria: eye opening, verbal response, motor response. -Based on scale of 0-15 with a higher score indicating a better prognosis. -13+ associated with a good prognosis; 7- associated with a poor prognosis. -Exposure: Complete exposure of the patient to evaluate further, unknown damage

Answer 114

HPI, PMH, etc and physical exam

Answer 115

Clostridium Tetani

Answer 116

trismus - Lockjaw Risus Sardonicus - spasms causing smiling Aphagia - can't swallow

Answer 117

``` greater than 6 hours old, clinical signs of infection, deep, devitalized tissue, contamination, traumatic mechanism of injury, etc ```

Answer 118

- Unknown tetanus status: - Clean wound: Give the toxoid; Hold the TIG - Tetanus-prone wound: Give the toxoid; Give the TIG -Incomplete tetanus status: -Clean wound: Give the toxoid; Hold the TIG (No booster within 5 years) -Tetanus-prone wound: Give the toxoid; Give the TIG -Complete tetanus status: -Clean wound: Hold the toxoid; Hold the TIG (Booster within 5 years) -Tetanus-prone wound: Hold the toxoid; Hold the TIG

Answer 119

toxoid 0.5ml | TIG (tetanus immunoglobulin) 250 to 300 units

Answer 120

-All trauma patients are potential surgical candidates, so get this information for the weenie anesthesiologists -Traditional guidelines recommend: -Nothing by mouth after midnight the night before elective surgery -Nothing by mouth within 6-8 hours of any type of surgery -These strict guidelines are in the process of changing however, particularly with regard to allowing the ingestion of small amounts of clear liquids up to the time of surgery

Answer 121

- Infection with emphysema (gas gangrene) - Open fracture/dislocation - Compartment syndrome - Necrotizing Fasciitis - General Neurovascular compromises

Answer 122

- Based on 4 criteria: Skeletal/Soft Tissue Injury, Limb Ischemia, Age, and Shock - Based on a scale from 1-11 with a higher score leading to an increased incidence of amputation. - A score of 7+ has an increased likelihood of amputation.

Answer 123

-Note that 30% of lower extremity open fractures are associated with polytrauma. -Mainstays of treatment: Aggressive incision and drainage with copious lavage. -It is generally recommended to never primarily close an open fracture until devitalized soft tissue has demarcated, but this certainly isn’t always the case in practice. In fact, the Ortho Trauma service at Inova routinely primarily closes open fractures following I&D with ORIF.

Answer 124

I. Clean Wound 5cm in diameter with extensive soft tissue damage - Abx choice: Ancef (or high dose PCN), Clindamycin and Aminoglycoside - IIIA: Adequate soft tissue coverage - IIIB: Extensive soft tissue damage with periosteal stripping and massive contamination - IIIC: Arterial damage requiring primary repair

Answer 125

-Location: Subepidermal -Note that the fluid is sterile. Fracture blisters are histologically similar to 2nd degree burns. -Most common LE etiology? Secondary to high-energy trauma such as ankle fx, calcaneus fx or Lisfranc injury. -2 Common Types of Fracture Blisters -Clear fluid: Most common (75%). Very tense in appearance. -Hemorrhagic: Most severe. Roof is flaccid. Takes longer to re-epithelialize. -Treatment is controversial, but the conservative approach is to never incise through a fracture blister and to delay surgery until re-epithelialization

Answer 126

``` Tachycardia, Tachypnea, delayed capillary refill, decreased pulse pressure, change in mental status, decreased systolic pressure, decreased urinary output decreased H&H ```

Answer 127

-Hypovolemic: most common; defined as the acute loss of circulating blood. Treatment is aggressive fluid replacement. -Cardiogenic: induced by myocardial dysfunction. -Neurogenic: secondary to decreased sympathetic tone from head and spinal cord injuries. -Septic: shock secondary to infection

Answer 128

Restore organ perfusion

Answer 129

-Clinical signs of infection, known contaminated object, pain, object close to NV elements, intra-articular

Answer 130

-Plain film radiography (no oblique views!), fluoroscopy, CT, MRI, US

Answer 131

-Hyperechoic with a hypoechoic dark shadow

Answer 132

A piece of glass, regardless of whether it is leaden, must be >5mm to be visibl

Answer 133

- Resnick Classification | - Patzakis Classification

Answer 134

- I. Superficial/cutaneous: usually visible without signs of infection. - II. Subcutaneous or articular without signs of infection. - IIIA. Subcutaneous or articular with signs of infection. - IIIB. Bone penetration without signs of infection. - IV. Bone penetration with known osteomyelitis.

Answer 135

Wound site as a predictore of complications following deep nail puctures of foot. - Zone 1: Toe to met head (50% incidence of osteomyelitis in this limited study.) - Zone 2: Midfoot (17% incidence of osteomyelitis in this limited study.) - Zone 3: Calcaneus (33% incidence of osteomyelitis in this limited study.

Answer 136

Staph Aureus Beta Hemolyitc strept

Answer 137

pseudomonas

Answer 138

Clostridia

Answer 139

Eikenella corrodens

Answer 140

pasteurella multocida

Answer 141

enterobacter pseudomonas Staph Bacillis

Answer 142

Tetanus status abx aggressive I& D lavage

Answer 143

-High velocity GSWs are characterized by speeds >2500 ft/s. This is significant because high velocity GSWs have a tendency to yaw and tumble leading to increased cavitation.

Answer 144

GSW Large wound is created under a situation of negative pressure. This negative pressure “sucks” outside contaminants into the wound

Answer 145

-Results when interstitial pressure exceeds capillary hydrostatic pressure, so the microcirculation shuts down

Answer 146

- P’s of Compartment Syndrome (These are very generalized) - Pain out of proportion and not controlled by analgesics -Paralysis - Pain with passive dorsiflexion of the toes -Pulselessness - Paresthesia -Pressure - Pallor

Answer 147

0 to 5 mmHg

Answer 148

- Decompression via fasciotomy, debridement of necrotic tissue, copious lavage and delayed closure - Incision approaches: Consider dorsal vs. medial approaches

Answer 149

wick or slit catheter to measure pressures

Answer 150

-Complications: permanent loss of function with structural deformity (Volkmann contractures), myoneural necrosis, sensory loss, chronic pain

Answer 151

-Intermetatarsal Compartments X 4: Contains the interossei muscles -Medial Compartment: Abductor Hallucis -Lateral Compartment: Abductor digiti minimi -Superficial Central Compartment: FDB -Deep Central Compartment: Adductor Hallucis -Calcaneal Compartment: Quadratus Plantae and late Dorsal: EHB and EDB

Answer 152

lie above fascial compartments so they are the last to go.

Answer 153

-History of trauma. “Bedpost” fracture describes stubbing your toe while walking at night. Also common are injuries from dropping objects on the foot

Answer 154

- Edema, erythema, ecchymosis, open lesions, subungual hematoma, and onycholysis should all be expected. - Any rotational/angulation deformities should be identified on plain film radiograph.

Answer 155

- Rosenthal Classification [Rosenthal EA. Treatment of fingertip and nail bed injuries. Orthop Clin North Am. 1983; 14: 675-697.] - Zone I: Injury occurs with damaged tissue completely distal to the distal aspect of the phalanx. - Zone II: Injury occurs with damaged tissue completely distal to the lunula. - Zone III: Injury occurs with damaged tissue completely distal to the most distal joint (IPJ in hallux; DIPJ in lesser) .

Answer 156

- Zone I Injuries - If injury involves no exposed bone and a total tissue loss less than 1cm squared, then: - Allow to heal in by secondary intention. - If injury involves a total tissue loss greater than 1cm squared, then: - A STSG or FTSG should be used depending on weight-bearing position. - Zone II Injuries - Flaps and Skin Grafts generally employed: - Atasoy flap: plantar V to Y advancement -Kutler flap: biaxial V to Y advancement - Zone III Injuries - Usually requires distal amputation (Distal Symes amputation)

Answer 157

immobilization

Answer 158

25% incidienc of underlying phalanx fracture

Answer 159

remove nail

Answer 160

5mm of lunula

Answer 161

beau's line

Answer 162

-History of trauma is very important in this case. You want to differentiate between acute and chronic conditions involving the sesamoids. Be careful to elicit any neurologic complaints that could be present

Answer 163

-Expect edema, erythema, ecchymosis and open lesions. Take the time for proper palpation. -Joplin’s neuroma is irritation of the medial plantar proper digital nerve. -Associated with rigidly plantarflexed first metatarsals, anterior cavus, etc. -One of the most difficult things to differentiate is an acute sesamoid fracture from a bipartite sesamoid. There are several generic plain film radiographic characteristics found in acute fractures: -Jagged, irregular and uneven spacing -Large space between fragments -Abnormal anatomy -Bone callus formation -Comparison to a contra-lateral view

Answer 164

- Type I - Mechanism: Dorsal dislocation of the hallux - Intersesamoid ligament: Intact - Fracture?: No sesamoid fracture - Treatment: Requires open reduction - Type IIA - Mechanism: Dorsal dislocation of the hallux - Intersesamoid ligament: Ruptured - Fracture?: No sesamoid fracture - Treatment: Closed reduction/Conservative Care - Type IIB - Mechanism: Dorsal dislocation of the hallux - Intersesamoid ligament: Ruptured - Fracture?: Fracture of at least one sesamoid - Treatment: Closed reduction/Conservative Care - Type II Variant - Mechanism: Dorsal dislocation of the hallux - Intersesamoid ligament: Ruptured - Fracture?: Separation of a bipartite sesamoid - Treatment: Closed reduction/Conservative Care

Answer 165

- Conservative - Immobilization (NWB SLC, PWB SLC, Surgical Shoe, CAM Walker, etc.) - Dancer’s Pad - Surgical - Excision of the fractured fragment or entire sesamoid

Answer 166

Ilfeld's disease

Answer 167

35. 5% (kewenter) | 10. 7% (Inge) with 75% being unilateral

Answer 168

-Will point to some form of traumatic injury. Common injuries leading to metatarsal fracture include direct blunt trauma, shearing, ankle sprains, etc. -Most important in your work-up will be how you read the plain film radiographs. Remember that at least two views are necessary to accurately describe displacement/angular/rotational abnormalities

Answer 169

-MOI: Direct or indirect trauma - Radiographic findings: - Examine for evidence of displacement/angulation/rotation - Expect a shortening mechanism - Examine for intra-articular nature of fracture - Treatment: - Conservative - Closed reduction generally unsuccessful - Surgical - ORIF with fixation of K-wire, screws or absorbable pins - Immobilization for 4-6 weeks and NWB - Follow-Up - Early PROM suggested - Subsequent arthrosis is a common complication

Answer 170

-MOI: Shearing forces or direct trauma - Radiographic findings: - Expect elements of shortening, plantarflexion and lateral displacement of the distal segment. -Treatment: -Conservative --Closed reduction generally unsuccessful -Surgical --ORIF effective in restoring and maintaining alignment with K-wires, IM pinning and plates. -Follow-up --NWB in SLC for 4-6 weeks -

Answer 171

Adjacent fractures generally improve alignment after reduction of the initial fracture because soft tissue structures are returned to their normal position through traction.

Answer 172

-MOI: Result of direct, blunt or torsional injuries - Radiographic findings: - Expect oblique fracture line, but transverse, spiral and comminuted are all possible. - Expect elements of shortening, plantarflexion and lateral displacement of the distal segment. - Treatment: - Based on displacement and fracture type: - Non-displaced fractures: NWB SLC 4-6 weeks - Fractures with >2-3mm of displacement and >10 degrees of angulation: ORIF - Transverse displaced fractures - Consider buttress plate, compression plate, IM percutaneous pinning, crossed K-wires - Long oblique or spiral fractures - Consider screws, plates, IM pinning, cerclage wiring - Comminution - Consider screws, plates, cerclage wiring, K-wires and external fixation

Answer 173

``` -MOI: Direct trauma (MVA, fall from height, etc.) Usually associated with Lisfranc’s trauma. ``` -Radiographic findings: -Generally remain in good alignment/angulation because of surrounding stable structures. - Treatment: -Conservative - NWB SLC 4-6 weeks with good alignment - Surgical - ORIF with displacement/alignment/angulation

Answer 174

``` -MOI: Direct trauma (MVA, fall from height, crush, etc.) and indirect trauma (torsional, twisting, avulsions, etc.) ``` - Radiographic findings: - Variable - Examine for distal intra-articular fractures - Examine for avulsion-type fractures - Treatment: - Conservative - SLC 4-6 weeks with non-displaced fractures - Be wary of closed reduction because extrinsic muscles may displace after apposition. - Surgical - Various ORIF techniques detailed above - Percutaneous pinning and cannulated screws are option in first metatarsal - ORIF should be utilized if intra-articular fracture involves >20% of articular surface

Answer 175

-All will point to some form of traumatic injury. Common injuries leading to metatarsal fracture include direct trauma, blunt trauma, shearing, ankle sprains, etc. -Most important in your work-up will be how you read the plain film radiographs. Remember that at least two views are necessary to accurately describe displacement/angular/rotational abnormalities.

Answer 176

Extra-articular fx at metaphyseal-diaphyseal junction (True Jones Fracture) -MOI: Internal rotation of the forefoot while the base of 5 th met remains fixed -Radiographic findings: -Usually oblique or transverse fx at metaphyseal-diaphyseal junction -Treatment: -NWB SLC 4-6 weeks for non-displaced fractures -ORIF with displacement >5mm -Misc: -Fracture first described by Sir Robert Jones in 1902 from injuring himself while ballroom dancing. -Very unstable fracture with high incidence of non-union/delayed union secondary to variable blood supply. Remember that the diaphysis and metaphysis are generally supplied by two different arterial sources.

Answer 177

Intra-articular avulsion fracture - MOI: Shearing force caused by internal twisting with contracture of peroneus brevis tendon - Radiographic findings: -1 or 2 fracture lines - Intra-articular in nature - Treatment: -NWB SLC 4-6 weeks for non-displaced fractures - ORIF with displacement >5mm

Answer 178

- MOI: Reflex contracture of peroneus brevis with ankle in plantarflexed position - Radiographic findings: -Extra-articular; Involvement of styloid process - Treatment: -NWB SLC 4-6 weeks for non-displaced fractures - ORIF (pins, screws, tension-band wiring) for displacement >5mm - Consider excision of fragment and reattachment of peroneus brevis tendon

Answer 179

Intra-articular, Comminuted fracture -MOI: Crush injuries with base of 5 th met stuck between cuboid and the external agent -Radiographic findings: -Multiple fragments; joint involvement -Treatment: -NWB SLC 4-6 weeks for non-displaced fractures -ORIF with displacement -Consider bone grafting and fragment excision with severe comminution -Misc: -High rate of non-union/delayed union

Answer 180

Extra-articular avulsion fractures of the epiphysis - MOI and treatment similar to Type II and III fractures - Note that this can only occur in children (similar to a Salter-Harris Type I fracture)

Answer 181

- Radiographic classification of Jones fractures describing potential for non-union development. - Type I: Acute injuries - Radiographic findings: Narrow fracture line without intra-medullary sclerosis - Type II: Delayed Union - Radiographic findings: Widened fracture intersurface with evidence of IM sclerosis - Type III: Non-Union - Radiographic findings: Complete sclerotic obliteration of the IM canal

Answer 182

March fx, Hairline fx, Fatigue fx, Insufficiency fx, Deutschlander’s dz, Bone exhaustion, etc

Answer 183

-CC: Patient presents complaining of a diffuse foot and ankle pain. Classic patient is a military recruit or athlete. -HPI: -Nature: Pain described as “sharp with WB” or “sore/aching.” May have element of “shooting” pain. -Location: Described as diffuse, but can be localized with palpation. Common areas include dorsal metatarsal or distal tib/fib. -Course: Subacute onset. Usually related to an increase in patient’s physical activity. -Aggravating factors: Activity -Alleviating factors: PRICE -PMH: -Look for things that would weaken bone (eg. Osteoporosis) -SH: -Look for recent increases in physical activity or a generally active patient -PSH/Meds/All/FH/ROS: Usually non-contributory

Answer 184

Physical Exam - Derm: -Generalized or localized edema - Ecchymosis is rare - Vasc/Neuro: Usually non-contributory - Ortho: -Painful on localized palpation (positive pinpoint tenderness!!) - Possible pain with tuning fork

Answer 185

-Plain Film Radiograph: -Localized loss of bone density and bone callus formation are hallmark signs -Note that there must be a 30-50% loss of bone mineralization before radiographic presentation of decreased bone density. This generally takes 10-21 days in a stress fracture. -Bone Scan: -Increased uptake in all phases regardless of time of presentation

Answer 186

metatarsals (2nd most common) and distal tib/fib

Answer 187

- Chronic strain upon a normal bone | - A chronic, normally benign strain upon a weakened bone

Answer 188

- Immobilization and NWB for 4-6 weeks (SLC, Unna boot, surgical shoe, etc.) - Be certain of anatomic position with no angulation/rotation/displacement (very uncommon)

Answer 189

-Dr. Jacques Lisfranc was a French gynecologist who was called into the service of Napoleon’s army where he served as a trauma surgeon in the 1820’s and 30’s. He also served under Dr. Dupuytren during this time. -Del Sel first described Lisfranc dislocations following equine injuries (JBJS 1955).

Answer 190

-Tarsometatarsal joint: 9 bones, ~13 joints, 7 weak dorsal ligaments, 5 strong plantar ligaments, the Lisfranc ligament (+2 other interosseous ligaments) -Myerson described three functional columns of the Lisfranc joint. Ouzounian and Shereff described the sagittal plane motion of each of these columns. -Medial Column: 1st met and medial cuneiform: 4mm of motion in the sagittal plane. -Central Column: 2 nd /3 rd mets and central/lateral cuneiforms. 1mm of motion in sagittal plane. -Lateral Column: 4 th /5 th mets and cuboid. 10mm of motion in the sagittal plane.

Answer 191

- Accounts for 0.2% of all traumatic injuries. Most common in MVA and sports injuries. - Occurs either by direct crushing (i.e. dropping something on the foot) or indirectly (usually a plantarflexed and abducted foot).

Answer 192

- Midfoot pain and tenderness. Possibly exacerbated with pronation, abduction or plantarflexion. - Plantar ecchymosis - Be wary of compartment syndrome! Always check neurovascular status

Answer 193

-Plain Film Radiography -Pathognomonic “fleck sign” representing an avulsion fx in the 1st IM space. -Look for deviations from normal in the AP, MO and Lat views. Normal is: -AP: Medial border of the 2 nd met continuous with the medial border of the central cuneiform. Lateral border of the medial cuneiform continuous with the medial border of the central cuneiform. -MO: Medial border of the 4th met continuous with the medial border of the cuboid. Lateral border of the 3rdmet continuous with the lateral border of the lateral cuneiform. -Lat: No sagittal displacement. Look for lateral column shortening with a “nutcracker fracture” of the cuboid. -“Lisfranc variant” is fracture damage extending proximally into the cuboid-navicular region. -Consider stress radiographs with the foot in plantarflexion or abduction

Answer 194

Myerson originally called Quenu and Kuss the modified by Hardcastle

Answer 195

-Type A: Total incongruity in any plane (QK: Homolateral) -Type B: Partial incongruity (QK: Isolateral) -B1: 1stmet goes medial -B2: Lesser mets go lateral -Type C: Divergent (QK: Divergent) -C1: Partial (only 1st and 2nd mets involved) -C2: Total (all mets involved)

Answer 196

-Literature strongly favors ORIF with any displacement (>2mm between the 1st and 2nd mets). Exact anatomic reduction is the key to prognosis.

Answer 197

-If plain film and stress radiographs show no displacement, then NWB SLC for 6 weeks with films q2 weeks looking specifically for displacement.

Answer 198

-Goal: Reduction and stabilization of the medial and central columns. You must reduce the lateral column, but it is usually left unfixed because of the pronating mobile adapter mechanism. The medial and central columns do not have as much sagittal plane motion, but you still don’t want excess compression with associated chondrolysis to develop. -Fixation: -1st met to medial cuneiform, 2nd met to central cuneiform, and 3rd met to lateral cuneiform with crossed 0.062” K-wires (removed at 8 weeks), cannulated cancellous screws (removed at ~12 weeks) or 3.5mm corticals. Consider putting a notch 1.5cm distal to the joint for screw to prevent stress risers. Drill the hole for the screw in the superior aspect of the notch and not the base to prevent splitting the base. -Consider 4th met to cuboid and 5th met to cuboid with a single 0.062” K-wire -Lisfranc Screw: Medial cuneiform to 2nd met base, screw in a lag fashion -Length of the lateral column must be restored following a “nutcracker fracture.” Consider using an H-plate or external fixation. -Incisions: -Usually longitudinally over the dorsal-medial 1 st , proximal 2nd interspace (for access to 2,3) and proximal 4th interspace.

Answer 199

-NWB SLC for 8 weeks transitioned to PWB SLC for 4 weeks transitioned to rehab. High impact activity can usually be resumed at 6 month

Answer 200

ARTHROSIS! essentially everyone develops post-traumatic arthritis to some extent

Answer 201

-History of trauma ranges from contusions to ankle sprains to forced abduction/plantarflexion of the forefoot

Answer 202

-Manual muscle testing (MMT) of the posterior tibialis tendon is important in these cases. -Multiple view plain film radiographs are extremely important because of the possible obliquity of some fractures. CT scans and MR images may also be necessary for complete visualization and analysis of stress fractures.

Answer 203

-The navicular is surrounded by a number of joints of varying stability. The TNJ proximally is very mobile, while the distal NCJ and lateral NCJ are very stable. The navicular is also very stable medially because of the insertion of the PT tendon. -Vascular anatomy to the navicular can be extremely important as described by Sarrafian: -It has been demonstrated that the central 1/3 of the navicular is relatively avascular. -The dorsalis pedis artery adequately supplies the dorsal and medial aspects. -The medial plantar artery adequately supplies the plantar and lateral aspects. -The central 1/3 has variable, radially-projecting branches from anastomosis of these arteries

Answer 204

I - Nav Tuberosity fx II - Dorsal Lip avulsion fx III - Navicular body fx --IIIA - Coronal Plane fx with no angulation --IIIB - Dorso-lateral to Plantar Medial fx with adduction of the forefoot ---IIIC -Comminuton with abduction of the forefoot IV - Stress fracture of navicular

Answer 205

- Type I: Navicular Tuberosity Fractures - Occur secondary to eversion and posterior tibialis contracture - Watch for associated “nutcracker fracture” of cuboid and anterior calcaneal process fractures - Must be differentiated from accessory navicular - Treatment: - Displacement 5mm consider: - Excision of fragment with reattachment of tendon - ORIF with a cancellous screw

Answer 206

- Type II: Dorsal Lip Avulsion Fractures - Occur secondary to plantarflexion/frontal plane mechanisms. - Must differentiate from os supranaviculare and os supratalare accessory ossicles. - Generally intra-articular - Generally treated with conservative immobilization

Answer 207

Navicular Body Fractures. Described by Sangeorzan. - [Sangeorzan BJ, et al. Displaced intra-articular fractures of the tarsal navicular. JBJS-Am. 1989; 71(10): 1504-10.] - IIIA: Coronal Plane Fracture with no angulation - ~100% successful reduction usually achieved - IIIB: Dorso-lateral to Plantar-medial fracture with adduction of the forefoot - 67% successful reduction usually achieved - IIIC: Comminution with abduction of the forefoot - 50% successful reduction usually achieved

Answer 208

- Must achieve 60% reapproximation of proximal joint space - Incision placed dorsal-medial, between the TA and TP - Complications involve post-traumatic arthritis and/or AVN

Answer 209

- Fixation Options using 3.5mm Cortical Screws: - Two screws directed lateral to medial - Two crossed screws directed proximal to distal - One screw directed proximal-medial to distal-lateral into the middle cuneiform - Consider FDL transfer in the presence of a weakened PT tendon

Answer 210

- Generally occurs secondary to running - Torg describes typical stress fracture occurring in central 1/3 of body in the sagittal plane. - DDx: Tibialis anterior tendonitis - Usually plain films, CT and bone scans are necessary to diagnose

Answer 211

-Talar fractures are generally associated with high energy trauma, and a standard evaluation with primary and secondary surveys should precede any specific talar evaluation. The following describes unique subjective findings, objective findings, diagnostic classifications and treatment considerations.

Answer 212

-History of trauma with a high incidence of MVC. The classic description of a talar neck fracture comes from a forced dorsiflexion of the foot on the ankle (“aviator’s astragulus”). Talar fractures account for approximately 1% of all foot and ankle fractures.

Answer 213

-Important to verify neurovascular status, and rule out dislocations and compartment syndromes

Answer 214

-Canale View: Plain film radiograph taken with the foot in a plantarflexed position. The foot is also pronated 15 degrees with the tube head orientated 75 degrees cephalad. This view allows for evaluation of angular deformities of the talar neck. -CT scan is essential for complete evaluation and surgical planning.

Answer 215

- Dorsalis Pedis: Supply the superior aspect of the head and neck (artery of the superior neck) - Anastomoses with the peroneal and perforating peroneal arteries - Artery to the sinus tarsi: supplies the lateral aspect of the talar body - Forms an anastomotic sling with the artery of the tarsal canal - Posterior Tibial Artery: - Deltoid branch: medial aspect of the talar body - Artery of the canalis tarsi: majority of the talar body - Forms an anastomotic sling with the artery of the tarsal sinus - Also sends branches to the posterior process - Peroneal/Perforating Peroneal Artery: supplies posterior and lateral aspects of the talar body - Anastomoses with the dorsalis pedis artery branches

Answer 216

Hawkins Berndt Hardy Sneppen Modified Hawkins

Answer 217

Hawkins Classification: Talar neck fractures Type I: Non-displaced (~13% incidence of AVN) Type II: Displaced fracture with STJ dislocation (~50% incidence) Type III: Displaced fracture with STJ and ankle dislocation (~95%) Type IV: Displaced fracture with STJ/ankle/TN dislocation (>95%) -(Type IV added by Canale and Kelly)

Answer 218

Berndt and Harty: Talar dome fractures Type 1: Chondral Depression Type 2: Partial chondral fracture, seen on MRI Type 3: Nondisplaced complete osteochondral fracture Type 4: Displaced complete osteochondral fracture

Answer 219

Sneppen: Talar body fractures Type 1: Osteochondral fracture Type 2: Sagittal, Coronal, Transverse body fracture Type 3: Posterior tubercle fracture Type 4: Lateral process fracture Type 5: Crush fracture

Answer 220

Modified Hawkins: Lateral process fractures Type I: Simple bipartite fracture Type II: Comminuted fracture Type III: Chip fracture of anteroinferior lateral process

Answer 221

Shepheds fracture

Answer 222

Cedells fracture

Answer 223

lateral process fracture

Answer 224

- NWB in SLC 6-8 weeks versus ORIF depending on nature of fracture and degree of displacement. - Titanium hardware may be used so that MRI evaluation may be used in post-operative period to evaluate for AVN!

Answer 225

-Hawkins sign: radiolucency of the talar body noted at 6-8 weeks after fracture. This sign is indicative of intact vascularity. However, the absence of this sign does not indicate that osteonecrosis and talar collapse are eminent.

Answer 226

-Demographics: Men>Women; Age range generally 30-60; account for ~2% of all fractures; 2-10% are bilateral; 10% associated with vertebral fracture (most commonly L1); 1% associated with pelvic fracture and urethral trauma

Answer 227

Direct axial load, vertical shear force, MVC, gastroc contraction, stress fracture, ballistics, iatrogenic surgical fracture

Answer 228

height back pain compartment syndrome

Answer 229

- Pain with palpation to heel - Mondor’s Sign: characteristic ecchymosis extending into plantar medial foot - Short, wide heel - Hoffa’s sign: less taut Achilles tendon on involved side - Inability to bear weight -Must rule out compartment syndrome - Imaging: -Plain film Imaging: -Bohler’s Angle: normally 25-40 degrees (decre

Answer 230

- Bohler’s Angle: normally 25-40 degrees (decreased with fracture) - Critical Angle of Gissane: normally 125-140 degrees (increased with fracture) - Both demonstrate loss of calcaneal height - Broden’s View: Oblique views to view the middle and posterior facets - Isherwood Views: 3 oblique views to highlight all facets - Calcaneal Axial View: demonstrates lateral widening and varus orientation - CT Scan: -Gold standard for evaluation and surgical planning - The coronal view forms the basis of the Sanders Classification

Answer 231

- Type I: Non-displaced articular fx - Type II: Two-part posterior facet fx - Type III: Three-part posterior facet fx - Type IV: Four-part/comminuted fx - A, B and C further describe the fx (lateralÆmedial) - A/B: divide posterior facet into equal 1/3’s - C: divides posterior facet from sus tali

Answer 232

- Type I: -Type IA: Plantar tuberosity fractures (medial more common than lateral) - Type IB: Sus tali fracture (remember FHL: pt will have pain with hallux PROM) - Type IC: Anterior process fractures (remember your anatomy: bifurcate ligament) - further divided into three parts by Degan Classification - Type II: -Type IIA: Extra-articular “beak” fracture of posterior-superior calcaneal body - Type IIB: Intra-articular “tongue-type” Achilles avulsion fracture - Type III: Extra-articular calcaneal body fracture - Type IV: Intra-articular joint depression fracture - Type V: Intra-articular comminuted fracture

Answer 233

-Differentiated between extra-articular (~25%) and intra-articular (~75%) fractures and further sub-divided intra-articular fractures into tongue-type and joint depression fractures (both with the same primary force, but different secondary exit points).

Answer 234

- Assigns 2-12 points based on: - Number of fragments - Number of involved joints - Open fracture or high soft tissue injury - Highly comminuted nature, or associated talar, cuboid, navicular fracture

Answer 235

Restore calc height decrease widening take it out of varus Articular reduction

Answer 236

lateral extensile surgical approach

Answer 237

``` wound healing arthritis! lateral ankle impingement malunion nonunion ```

Answer 238

-The standard trauma work-up again applies with primary and secondary surveys. The following describes unique subjective findings, objective findings, diagnostic classifications and treatment considerations. -Residents and attendings love to ask questions about ankle fractures for whatever reason, so this is certainly a subject where you should know the classification systems cold, and do a lot of the additional readings. We’ll keep it brief here

Answer 239

-Lateral: ATFL, CFL, PTFL -Medial: Superficial Deltoid: superficial talotibial, naviculotibial, tibiocalcaneal ligaments Deep Deltoid: anterior talotibial and deep posterior ligaments

Answer 240

AITFL, PITFL (and inferior transverse tibiofibular ligament), Interosseous ligament

Answer 241

-Developed by ED docs to minimize unnecessary radiographs following ankle sprains. X-ray only required if: -Bone tenderness along distal 6cm of posterior edge of fibula or tibia -Bone tenderness at tip of fibula or tibia -Bone tenderness at the base of the 5 th met -Bone tenderness on the navicular -Inability to bear weight/walk 4 steps in the ED

Answer 242

for medial malleolor fx A - avulsion B- transvers at level of mortise C - Oblique D - Vertical

Answer 243

Infrasyndesmotic A1 - isolated A2 - with medial mall A3 - with post-medial mall B - Transysdesmotic B1 - Isolated B2 - With medial mall fx or deltoid B3 - with media lesion and poserolateral tibial fx C - Suprasyndesmotic C1 - simple diaphyseal fibular fx C2 -Complex diaphyseal fibular fx C3 - Proximal fib fx

Answer 244

AITFL avulsion from the anterolateral tibia

Answer 245

AITFL avulsion from the anteromedial fibula

Answer 246

PITFL avulsion for postlat tibia

Answer 247

PITFL avulsion from the posterior-medial fibula

Answer 248

Weber C-type proximal fibular fracture that occurs within 10cm of the fibular neck

Answer 249

Generic term for a bimalleolar ankle fracture

Answer 250

Generic term of a trimalleolar ankle fracture

Answer 251

At least a bimalleolar fracture when the talus gets lodged up between the tibia and fibula

Answer 252

Different than an avulsion fracture of the PITFL; this is a true fx involving a portion of the tibial plafond cartilage. CT is usually done to estimate a percentage of the involved joint space. The rule of thumb (although certainly not proven) is that fractures involving >25-30% of the joint space require ORIF.

Answer 253

Restore fib length Restore ankle mortise Fix syndesmosis

Answer 254

-Most people agree that the fibular fracture is the dominant fracture. In other words, if you adequately reduce the fibula, then the other fractures and dislocations more or less fall into line because of the soft tissues (poor man’s definition of the Vassal Principle). It doesn’t mean that the other fractures don’t require fixation, but it means there’s no real sense in fixating the other fractures unless you have the dominate fracture fixated (or at least reduced). -The other concept is that a fixed fibula is essentially acting as a buttress, keeping the talus within the ankle mortise. -The fibula is generally shortened in ankle fractures, so you want to get the full length back with your reduction (generally visibly seen by reduction of the posterior spike on a lateral view)

Answer 255

-This goes back to the fibula keeping the talus in the ankle mortise. The classic article you need to know is Ramsey and Hamilton that showed a 42% decrease in the tibiotalar contact area when the talus was displaced 1mm laterally. From this, people inferred that if the talus isn’t perfectly reduced back into the mortise, then gross instability occurs. -This is assessed by: -Medial clear space (from the talar shoulder): Should be ~4mm or less after reduction -Tib-Fib Overlap: Approximately >10mm on AP view at 1cm superior to the joint line -Talar Tilt: <5 degrees compared to other side

Answer 256

-Another area of controversy where there is no clear answer is when and how to fixate the syndesmosis with internal fixation. One point is clear: the purpose of placing internal fixation across the syndesmosis is to stabilize the fibula against the tibia to prevent lateral migration of the talus and instability. If the fibula is stable against the tibia with all of your other fixation, then you don’t really need any additional fixation. How can you tell? Radiographic findings and the Cotton hook test for instability intra-operatively. -Other questions where people have opinions, but no clear answers are: What type of screws? How many screws? How many cortices? How far above the ankle? Temporary vs. permanent fixation? Weightbearing? etc.

Answer 257

- Fracture is primarily reduced and fixated with a single 2.7 or 3.5mm cortical screw with interfrag compression. - Then a generic 1/3 tubular plate or a specialized contoured plate is used for buttress stabilization. - Attempt for 6 cortices proximal to fracture with 3.5 bicortical screws - Get as many distal screws as you can. 3.5 bicortical if above the ankle joint. 4.0 unicortical if not. - Proximal fibular fractures still amendable to 1/3 tubular plating, but may need to double-stack the plates. - Should appreciate the concept of lateral vs. posterior anti-glide plating

Answer 258

-Several options including 4.0 cancellous, K-wires, plating, cerclage, etc

Answer 259

-Tendon is actually the strongest part of the muscle-tendon-insertion system. It is much more likely for the complex to fail at the myotendinous junction or at the tendinous insertion, but acute tendon injuries do occur. They are usually the result of direct trauma, or overload on an intrinsically weakened tendon. -Tension overload on a passive muscle -Eccentric overload on an actively contracting muscle -Laceration -Blunt Trauma

Answer 260

- Increased age: - increased cross-linking of collagen fibrils decreases tendon elasticity - decreased reaction time and muscular contraction speed - decreased vascularity - Sex: -M>F - Systemic inflammatory process: -RA, SLE, Gout, etc. -Underlying endocrine dysfunction: -Xanthoma (hyperbetalipoproteinemia), DM, Hyperparathyroidism secondary to renal failure, hyperthyroidism, infection, intratendinous calcifications, etc. -Medications: -Fluoroquinolones, Corticosteroids

Answer 261

- As with most tissue, there is a generalized inflammation, reparative and remodeling phase. - Week 1: Severed ends fill in with granulation tissue - Weeks 2-3: Increased paratenon vascularity; collagen fibril alignment - Week 4: Return to full activity without immobilization

Answer 262

-May see avulsions, soft tissue swelling, accessory bones/calcifications

Answer 263

- Radiopaque dye injected into tendon sheath and viewed on plain film radiograph - Technically difficult with many false positives and negatives

Answer 264

-Tendon normally appears hyperechoic to muscle on US. -Look for discontinuity of fibers, possible alternating hyperechoic/hypoechoic bands, and an area of intensely hyperechoic hematoma. -It is very important that the US head is held perpendicular to the long axis of the tendon.

Answer 265

-Tendon normally appears as a homogenous, well-circumscribed oval surrounded by fat on CT. It normally has a higher attenuation than muscle. -Will be able to appreciate discontinuity on CT with injury.

Answer 266

-T1: Tendons normally have a uniform low-intensity (very black). Will be uniform with variable high-intensity signal with injury. -T2: Tendons are normally relatively low-intensity. Will light up with high-intensity signal with injury

Answer 267

Any MRI signal shot at 55 degrees to the course of | the tendon will show a false-positive damage signal. Very common in the peroneals

Answer 268

-It is possible, but rare to get acute tendon injury to any of the long tendons of the leg. An Achilles tendon work-up will be featured in another AJM sheet, but realize there are some basic principles that apply to any tendon. -One is generally able to primarily repair the tendon. Non-absorbable suture is preferred. -Special attention should be paid to vascular supply. Remember that the majority of a tendon’s vascularity comes from the mesotenon, and therefore should be preserved as much as possible. -If primary repair is not possible, consider using lengthening tendon slides, tendon grafts, tendon transfers and biomaterials such as Graft-Jacket (allograft dermal tissue matrix) or Pegasus (equine pericardium) to restore the integrity of the tendon. -The goal of treatment should be to allow early PROM without gapping of the tendon

Answer 269

CC: Typical complaint is pain, weakness and swelling in the back of the leg following an acute injury. The typical patient is the “weekend warrior” type. This is a 30-50 y/o male participating in a strenuous athletic activity after a generally inactive lifestyle. HPI: Nature: Pain, weakness and swelling. Pain is surprisingly non-intense allowing the patient to ambulate. The patient may relate an audible “pop” or “snap”. They may also relate feeling like they were “kicked or shot” in the back of the leg. Location: Distal posterior leg. The left leg is more affected. Some people theorize that this has to do with the majority of people having right-handedness and a greater strength and proprioception of the RLE. Duration, Onset, Course: Acute onset with gradually progressive increase in swelling and edema. Mechanism of Action: -Three classic MOA are described: -Unexpected dorsiflexion with triceps contraction -Pushing off during WB with the leg extended (tennis lunge) -Violent dorsiflexion on a plantarflexed ankle -Also consider lacerations and blunt trauma Previous History: obviously more likely to re-rupture

Answer 270

-Inflammatory conditions: RA, SLE, Gout -Endocrine dysfunction: DM, Renal failure with hyperparathyroidism, hyperthyroidism, Xanthoma (hyperbetalipoproteinemia) -Infection: Syphilis

Answer 271

Meds: -Corticosteroid injection -Fluoroquinolone use SH: -Smoking -Sedentary lifestyle with weekend activity

Answer 272

``` Derm: -Posterior, Medial and Lateral Ecchymosis -Open lesion associated with laceration Vasc: -Posterior, Medial and Lateral edema Neuro: -Sural Neuritis Ortho: -Palpable gap (“hatchet strike defect”) -Positive Thompson test -Negative Jack’s test -Pain in the area -Increased PROM ankle dorsiflexion -Decreased AROM ankle plantarflexion -Retraction of proximal gastroc belly -Apropulsive gait ```

Answer 273

-Mattles test: Foot should be in plantarflexed position with patient prone and knee at 90° - Simmonds’ test: Foot should be in plantarflexed position with patient prone - Various needle tests (O’Brian, Cetti) -Toygar’s skin angle: Normally 110-125 degrees. Increases to 130-150 degrees with rupture

Answer 274

- Plain film: - r/o Rowe Type IIB avulsion fracture - Radiodense gap - Obliteration of Kager’s triangle - Soft tissue edema - US: - Alternating hyperechoic and hypoechoic bands - Hyperechoic hematoma - MRI: - TI: -Ill-defined low-intensity with mixed high-intensity signal - T2: -High-intensity signal from hematoma

Answer 275

- Muscles of the Triceps Surae (origins, insertions, NV supply, action) - Plantaris (origins, insertions, NV supply, action) - Segmental Blood Supply of Tendon - “Twisting” of tendon

Answer 276

- Lagergren and Lindholm - Used microangiographic technique on human cadavers - Found decreased vascularity 2-6cm proximal to insertion - Theorized this was secondary to atrophy from inactivity - Conflicting information from laser Doppler flowmetry studies - Found uniform vascularity throughout tendon - Found decreased vascularity with age and in men - Found decreased vascularity with physical loading/stress of tendon, specifically at insertion - Leadbetter - Found increased stress/strain at the watershed area regardless of vascularity

Answer 277

-Type I: Partial tear involving 6cm deficit

Answer 278

-Peritendonitis: Inflammation of the surrounding tissues, not the tendon itself. This pain will remain stationary as the tendon is taken through a range of motion. -Tendonosis: Intra-tendinous degeneration. This pain will move proximally and distally as the tendon is taken through a range of motion. -Peritendonitis with tendonosis: combination of the two pathologies.

Answer 279

do nothing cast immobilize surgical repair

Answer 280

- AK cast versus SLC - Some are proponents of AK casting - Knee should be in a 20 degree flexed position - General recommendations: - Gravity equinus cast x 4 weeks - Reduction of 5 degrees every 2 weeks to a neutral ankle position (~4-6 weeks) - Heel lift and PT until normal ankle PROM - Return to full activity at approximately 6 months

Answer 281

- Midline to medial incision to avoid superficial neurovascular structures - Pt in a prone or supine frog-legged position - Use full-thickness flaps with emphasis on atraumatic technique

Answer 282

- Keith needles with non-absorbable suture (or fiberwire) with absorbable sutures to reinforce - There are three common stitches used: - Bunnell: Figure of 8 or weave stitch - Krakow: Interlocking stitch - Kessler: Box stitch

Answer 283

- Lynn: Plantaris is fanned out to reinforce - Silverskoild: 1 strip of gastroc aponeurosis brought down and twisted 180 degrees - Lindholm: Utilizes multiple strips of gastroc aponeurosis - Bug and Boyd: Strips of fascia lata are used to reinforce - VÆ Y lengthening of the proximal segment with primary repair - Reinforcement with FHL - Graft Jacket, Pegasus, etc.

Answer 284

Ma and Griffith described a bunnel type approach | may be associated with high re-rupture rates

Answer 285

SLC in gravity equinus over 6 to 10 weeks.

Answer 286

``` ADCVANDILMAX Admissio Diagnosi Condition Vitals Ambulataroy Staus Nursing Diet Ins/outs/ivs Labs Meds Ancillary consults X-rays/imaging ```

Answer 287

Pt is admitted to the general medical floor on the Podiatric Surgery Service under Dr. Attending. Most patients on the podiatric surgery service are admitted to the general medical floor or a surgical floor. Any pts admitted to a critical care unit or telemetry unit will probably be on a medicine service with a podiatric surgical consult.

Answer 288

Infection of bone of right 2 nd toe Always use terminology that everyone in the hospital can understand, but also be as specific as possible.

Answer 289

Stable Fair Guarded Critcal Most are stable or fair

Answer 290

Vitals recorded q8 hours per nursing. Recored how often Consider NV checks

Answer 291

-CBR (Complete bed rest) -As tolerated -NWB -OOB to chair -PWB Always designate which leg the order is for. Be specific with PWB status (“toe-touch” or “heel-touch”). If order is for CBR, consider DVT ppx and a bed pan order. If the order is OOB, specify # of times and length per day. Also consider Physical Therapy and/or Occupational Therapy orders here.

Answer 292

- Accuchecks (how often and when?) -Ice and elevation - Bedside Commode -Dispense Post-op shoe/Crutches - Wound Care -Dressing Instructions - Drain management -Off-loading instructions - Spirometry

Answer 293

- Regular diet - ADA 1800-2200 calorie - Mechanically soft - Renal diet - Cardiac diet - NPO - Decreased Na - Decreased K

Answer 294

- Measurement and recording of Ins and Outs (especially dialysis pts) - Foley - IV Fluids

Answer 295

- CBC with diff - Chem-7/Met Panel - Coags - Type and Screen - Wound cultures - Blood cultures - D-Dimer - HbA1c - CRP - ESR Always detail when the labs should be done. For example, initial CBC and Chem-7 should be taken “upon arrival to the floor.” Additionally, 2 sets of blood cultures should be taken from 2 different sites.

Answer 296

-Write out all at-home medications in full -Pain medication -Antibiotics -Insomnia -Anti-emetics -DVT ppx -Constipation -Diarrhea -Sliding Scale Insulin (SSI) -Fever -Throat lozenges -Anti-pruritic Be as specific as possible. SSI needs to be written out in full. Many medications require hold parameters. For example, fever medications should not be given unless the temperature reaches 101.5° F. Anti-HTN agents should be held if the blood pressure or heart rate drops too low

Answer 297

- General Medicine - Infectious Disease - Vascular Surgery - Cardiology - PT/OT - PM&R - Pulmonary - GI - Renal - Social Work - Home Care - Case Manager

Answer 298

``` Na: 135 to 145 K: 3.5 to 5 Cl: 95 to 105 Co2: 24 to 32 BUN: 5 to 20 Cr: 0.5 to 1/5 Glucose < 110 mg/dL ``` mEq/L

Answer 299

- Manifestations: Primarily neurologic, lethargy, headache, confusion, obtundation - Treatment: -Restrict water intake and promote water loss -Correct underlying disorder - Replace Na+ deficit

Answer 300

-Manifestations: Change in mental status, weakness, neuromuscular irritability, focal neurologic deficits, coma, seizures -Treatment: -Replace water loss and promote sodium excretion -Water deficit = ([Na+]-140)/140 x Total Body Water in liters -Rapid correction of either of these disorders is dangerous due to rapid shifts of water in and out of brain cells. It should therefore be corrected slowly over 48-72 hours. Aim correction at 0.5 mEq/L/hr with no more than a 12 mEq/L correction over the first 24 hours.

Answer 301

- Manifestations: Fatigue, myalgia, muscular weakness, cramps, arrhythmia’s, hypoventilation, paralysis, tetany - Treatment: -Minimize outgoing losses -Treat underlying cause - Correct K+ deficit via oral or IV means (K+ riders added to fluid, oral KCL, etc.)

Answer 302

-Manifestations: Cardiac toxicity (peaked T waves, prolonged PR, torsades de pointes), muscle weakness, paralysis, hypoventilation -Treatment: -Increase cellular uptake of K+ -Insulin (10-20 units) with 50 g IV glucose -IV NaHCO3 (3 ampules in 1L of 5% dextrose) -Albuterol (5-10mg nebulized over 30-60 minutes) -Increase K+ excretion -Loop diuretic, Thiazide diuretic -Kayexalate (cation exchange resin) (25-50mg mixed with 100ml 20% sorbitol to prevent constipation) -Dialysis -Calcium Gluconate (10ml of 10% solution over 2-3 minutes emergently to reduce membrane excitability

Answer 303

-Not going to talk much about this, but you should have a basic understanding of Acid-Base Regulation. -Equation for determining Anion Gap: Anion gap (all units mmol/L) = (Na + K) - (Cl + [HCO3-]) -Normal gap (~8-20mmol/L) -Negative/lowered gap (20mmol/L): Acidotic state -MUDPILES algorithm: methanol/metformin, uremia, diabetic ketoacidosis, propylene glycol, infection, lactate, ethanol, salicylate/starvation

Answer 304

-Measures of kidney function and hydration status -BUN (Blood Urea Nitrogen): Protein metabolism waste product eliminated by the kidneys. This can be increased if your kidneys aren’t eliminating it properly, or in a dehydrated state where it’s a relatively high concentration. -Creatinine: A more direct measure of kidney function from elimination of this skeletal muscle waste product. -Creatinine clearance and estimated glomerular filtration rate (GFR) with the Cockcroft-Gault Equation: [(140-Age in years) x Weight in kg] / [72 x Serum creatinine] x 0.85 if female -GFR < 60 ml/min indicates chronic kidney disease; < 15 indicates kidney failure -Antibiotics and other drugs should be dosed appropriately in these situations -Renal protective agents are utilized prior to procedures that are known to affect the kidneys in patients with kidney disease. A common example of this is an angiogram with dye to evaluate the vascular status of a patient with diabetic foot disease. -Pre-procedural hydration -Mucomyst (N-acetylcysteine) (also used for acetaminophen OD) -Sodium Bicarb Protocols

Answer 305

``` function of the immune system for a period of days, particularly cytokine activation and recruitment ```

Answer 306

Bind to β-cell receptors stimulating insulin release | -Glyburide (Micronase) -Glipizide (Glucotrol) -Glimepiride (Amaryl

Answer 307

Decrease production of glucose in the liver | -Metformin (Glucophage)

Answer 308

Increase peripheral cellular response to insulin | -Rosiglitazone (Avandia) -Pioglitazone (Actos)

Answer 309

Reduce intestinal carbohydrate absorption | -Acarbose (Precose) -Miglitol (Glyset

Answer 310

``` Lispro (Humalog) Aspart (Novolog) Onset 10-15 minutes 10-15 minutes Peak 1-2 hours 1-2 hours Duration 3-5 hours 3-5 hours ```

Answer 311

Regular 0.5-1hr 2-4 hours 4-8 hours

Answer 312

NPH Lente 1-3 hours 2-4 hours 4-10 hours 4-12 hours 10-18 hours 12-20 hours

Answer 313

Glargine (Lantus) Detemir (Levemir) 2-3 hours 1 hour None None 24+ hours 24 hours

Answer 314

70NPH | 30Regular

Answer 315

-There is increasing data that sliding scales are completely inefficient at in-patient glucose management. Sliding scales are passive, reactionary scales that compensate after a hyperglycemic incident occurs. Inzucchi recommends the following, instead of a sliding scale: -Basal Rate: Lantus or other long acting -Start 0.2-0.3 Units/kg/day; then increase 10-20% q1-2 days prn -Prandial Coverage: Novolog or other rapid acting -Start 0.05-0.1 Units/kg/day; then adjust 1-2 Units/dose q1-2 days prn

Answer 316

- 1/2 the normal dose of long acting if they get any - BG checks q6 hours with short acting agent available for coverage - D5W or D5-1/2NS at 50-75cc/hr while NPO

Answer 317

- Strongly consider an insulin drip - 1/2 – 2/3 normal dose of long acting agent - BG checks q6 hours with short acting agent available for coverage - D5W or D5-1/2NS at 75-100cc/hr while NPO

Answer 318

It can be used to maintain fluid balance in a patient who is NPO, correct electrolyte disturbances, and/or provide glucose to name just a few examples. This sheet will cover the basics of short-term maintenance therapy and show differences in electrolyte concentrations between the most common fluids.

Answer 319

- An NPO patient is still losing water that needs to be replaced to ensure homeostasis. Sources of water loss include: - Urine output: At least 500ml/day - Insensible water losses (Skin and Respiration): At least 500ml/day - This can increase by 150ml/day for each degree of body temperature of 37°C. - Gastrointestinal losses: Extremely variable - Direct blood volume loss from the surgery itself - Electrolytes are also lost to varying degrees. In the short term, it is usually only necessary to replace Na+, K+ and glucose. The other electrolytes usually do not need replacement until around 1 week of parenteral therapy.

Answer 320

- Pediatric patients should be aggressively rehydrated after a surgical procedure for two reasons: - They will lose a higher percentage of their total fluid volume during a procedure. - They have a tendency to “third space” and shift fluid balances in the perioperative period. - To determine the total intravascular volume of a pediatric patient: - The first 10kg of body weight account for about 80ml/kg. - So a 7kg kid would be (7x80) = 560ml - The next kg’s account for about 70ml/kg - So a 25kg kid would be (10x80 + 15x70) = 1850

Answer 321

-At the very least you should replace fluid to account for water loss. This is at least 1L/day, but you can certainly increase this and lose the excess through the urine. -It is also recommended to provide some electrolyte supplementation: -Na+: 50-150 mEq/day -K+: 20-60 mEq/day -Glucose: 100-150g/day to minimize protein catabolism and ketoacidosis

Answer 322

-Normal adult: NS or 1/2 NS or LR at 75-120ml/hr +/- 20mEq KCl -Diabetic patients: D5-1/2NS at 50-100ml/hr +/- 20mEq KCl while NPO There usually isn’t a need to deliver extra glucose (D5) to diabetic patients while they are PO

Answer 323

-The key to fluid management is an understanding and knowledge of exactly why you are giving fluids in the first place, what you hope to accomplish, what substances you are giving in the fluid and how much you are giving. -Obvious care needs to be taken with diabetic patients, those with renal pathology, and those with CHF.

Answer 324

-When dealing with a fever work-up, always note what the baseline temperature of the patient is and the method of measurement. -Fever in most institutions is defined as greater than 101.5° F. -Temperatures between 98.6-101.5° are low-grade fevers

Answer 325

- Inflammatory process of the surgical procedure itself - Pain - Transfusion Reaction - Malignant Hyperthermia - Pre-existing Sepsis

Answer 326

-0-6 hours post-op: Pain, anesthesia rxn, rebound from cold OR, endocrine causes (thyroid crisis, adrenal insufficiency) -24-48 hours post-op: atelectasis, aspiration pneumonia, dehydration, constipation -72+ hours: infection (3-7 days), DVT, UTI, drug allergy, thrombophlebitis

Answer 327

- 107: Anesthetic Hyperthermia - 106: --105: Blood transfusion reaction - 104: Closed abscess - 103: Atelectasis; pneumonia; drug reaction; liver disease - 102: Wound infection - 101: Draining abscess - 100: Benign post-op fever; post-anesthesia overshoot

Answer 328

Group a strep | Clostridium perfingens

Answer 329

-Dialysis patients typically run approximately 1 degree F cooler than the normal population, so a fever for HD patients wound be defined as 100.5° F. This is hypothesized to be due to a resetting of the hypothalamic set point

Answer 330

find the source

Answer 331

- Pain - Homan’s Sign: Pain in calf with dorsiflexion of the ankle - Pratt’s Sign: Pain with compression of the calf - Edema - Fever - SOB - Calor - Palpation of clot

Answer 332

- Hypercoagulable state - Immobilization - Vessel Wall Injury

Answer 333

``` -There is also the acronym I AM CLOTTED: Immobilization, Afib/CHF, Malignancy/MI, Coagulopathy, Longevity (age), Obesity, Trauma, Tobacco, Estrogen/BCP/HRT, DVT/PE history. ```

Answer 334

- Compression Ultrasound: can actually visualize the clot - D-Dimer > 500μg/ml: Not sufficient as a stand alone test - Consider full coagulation work-up for hypercoagulable states - Contrast venography - Impedance plethysmography

Answer 335

1. Prevent pulmonary embolism 2. Prevent clot extension 3. Prevent recurrence

Answer 336

- IV Unfractionated Heparin - Law of 8018 - Initial Dose 80mg/kg IV bolus and then 18mg/kg/hour - PTT should be checked q6 until it stabilizes at 1.5-2.5X normal (46-70s) - Goal is to get PTT in this range - LMWH may also be used - Enoxaparin (Lovenox): 1mg/kg subcutaneous q12 - Heparin Dosing Guide - Initial Dose: Law of 8018 with PTT checks q6 - If PTT 90s: Hold infusion for 1 hour, then decrease infusion rate by 3 units/kg/hr

Answer 337

- Warfarin (Coumadin) - Load at 10mg or 7.5mg PO qdaily for 2 days - Decrease/adjust dose to a target INR=2.5 - DO NOT stop heparin infusion until INR reaches 2.5 - INR should be maintained at 2.5 for 3-12 months - Consider placement of IVC filter (inferior vena cava)

Answer 338

- PE occurs when a clot from a peripheral location embolizes to the pulmonary vasculature - <25% of deep vein thromboses distal to the iliac veins go on to develop PE. - The more proximal the clot, the more likely it is to develop into a PE. - “Classic Triad” of signs and symptoms of a PE: Dyspnea/SOB, Chest Pain, Hemoptysis - Please note that less than 14% of patients experience the classic triad

Answer 339

- Gold standard: Pulmonary Angiography, Spiral CT - V/Q study - CXR

Answer 340

- Thrombolytic Therapy: - Urokinase: 4400units/kg IV over 10 min, then 4400units/kg/hr for 12 hours - Streptokinase: 1.5 million units IV over 60 minutes - Pulmonary Embolectomy - Various filter

Answer 341

- Plates and screws for fx fixation first described by Alain Lambotte in 1907. - Robert Danis (Belgium surgeon) published “The Theory and Practice of Osteosynthesis” in 1949. - Described use of compression plate called a coapteur. - Maurice Müller, a pupil of Danis, founded AO with other Swiss surgeons in 1958.

Answer 342

1. Accurate and precise anatomic reduction of fracture fragments (especially in joints). 2. Atraumatic surgical technique with emphasis on preservation of blood supply. 3. Rigid/Stable fixation 4. Early mobilization

Answer 343

generates compression which leads to lack ofmotion and therefore primary bone heali

Answer 344

Motion disrupts angiogenesis, decreases oxygen tension levels and inhibits osteogenesis. So, it is the lack of motion and NOT the compression that is osteogenic

Answer 345

- Orientation of the screw 90° to the fracture line obtains optimal compression. - >20° displacement from perpendicular is significant - Weakest in translation from axial loading - Orientation of the screw 90° to the long axis optimally prevents displacement with axial loading. - Weak in compression - Ideal screw placement for a long, oblique fracture: - One central anchor screw 90° to the long axis - One proximal and one distal compression screw 90° to the fracture line

Answer 346

- AO Recommendations: Overdrill, Underdrill, Countersink, Measure, Tap, Screw - Some underdrill before overdrill - Some don’t overdrill until after tapping - Two finger tightness = 440-770lbs. - To prevent thermal necrosis: - Sharp tip - Fast advancement (2-3mm/sec) - Slow drill speed (300-400rpm) - Firm force (20-25lbs) - Screw Pull-out - Directly proportional to screw diameter, screw length and bone strength (cortical nature). - Indirectly related to pilot hole diameter. - To increase screw pull-out, maximize bone-screw contact.

Answer 347

-Stress: pressure on a material -Strain: measurable deformation following a given stress -Fatigue Failure: failure from repetitive cyclic loading -Creep: temperature dependant permanent deformation of a metal -Stress Shielding: Internal fixation absorbs physiologic stress from bone and results in bone resorption per Wolff’s Law

Answer 348

- Elastic Range: -Non-permanent strain/deformation with a given stress - Proportional stress and strain (Hook’s Law) - Slope of the line is the stiffness (Young’s Modulus of Elasticity) - Yield Point: -Past the yield point, a given stress causes a non-proportional increase in strain. - Plastic Range: -Permanent deformation past the yield point - Ultimate Failure Point

Answer 349

-Head: more efficient hexagonal vs. cruciate -Land: underside of the head which contacts the near cortex. Want as much land-bone contact as possible to reduce stress at any one location. This is the same principle as washers and countersinking. -Shank: unthreaded portion of the screw -Run-out: junction between the shank and the threads. Represents the weakest portion of the screw. -Thread diameter: diameter of threads + core (major diameter) -Core diameter: diameter without the threads (minor diameter) -Pitch: distance between threads -Tip: can be round, trocar or fluted -Axis: central line of the screw -Rake Angle: thread to axis angle -Thread Angle: angle between the thread

Answer 350

- Cortical: tighter pitch designed for hard cortical bone (1.25mm) - Cancellous: higher pitch designed for metaphyseal and epiphyseal bone (1.75mm

Answer 351

-Fluted tip that clears debris as it is advanced -Require larger pilot holes, have decreased thread-bone contact and have the ability to cut its own path different from the underdrill

Answer 352

-Classically 3.0, 4.0, and 7.3mm, but really have just about any size available now -Advantages: self-drilling, self-tapping, good for hard to visualize fractures, avoids skiving of cortical bone on insertion and has definite co-axial nature with K-wire. -Disadvantages: hollow core, decreased thread-core ratio, decreased pull-out strength

Answer 353

- Proximal and distal threads separated by a smooth shaft. Headless. - Leading threads have increased pitch, so it draws the trailing threads. - Does generate interfragmental compression, but not a lot.

Answer 354

- FT, headless screw | - Prevents axial displacement. Does not generate compression.

Answer 355

-Essentially a self-cutting, PT cortical screw.

Answer 356

or use with screws from the mini fragment set

Answer 357

: For use with screws from the small fragment set

Answer 358

Wider/Deeper holes that allow for eccentric drilling and axial compression

Answer 359

Essentially grooves on the underside of the plate that limit periosteal contact

Answer 360

- Neutralization - Interfragmentary Compression - Buttressing - Tension Band

Answer 361

Ideally you want 3 or 4 cortical threads in each main fragment distally, and 5 or 6 proximall

Answer 362

Natural -pig gollagen, chromc Synthetic - Vicryl - Dexon - PDS - Maxon - Monocril

Answer 363

- Braided. May be coated (polyglactin 370 or calcium stearate) - 65% tensile strength at 14 days - Hydrolyzed (to CO2 and H20) in 80-120 days - Vicryl Rapid: Hydrolyzed in 42 days; loses strength in 7-10 days - Vicryl Plus: Coated with broad spectrum antibiotic Triclosan (also found in toothpaste

Answer 364

Braided | hydrolyzed 100 to 20 days

Answer 365

Monofilament 70% tensile strength at 14 days hydrolyzed in 90 dyas

Answer 366

Monofilament hydrolyzed in 180 dyas Longest lasting absorbable

Answer 367

- Monofilament - 20-30% tensile strength at 14 days - Hydrolyzed in 90-120 day

Answer 368

Natuarl - silk - cotton Synthetic - Nylon - Polypropylene - Polyester - Fiberwire - Stainless steel

Answer 369

Cotton/Linen

Answer 370

- Made from silk worm - Actually very slowly absorbed (hydrolyzed in 1 year) - Very low tensile strength

Answer 371

- Both monofilament and braided available | - Highest “knot slippage” rate: monofilaments are at a higher risk of knot slippage

Answer 372

Prolene, surgilene -Monofilament -Can be used in contaminated/infected wounds (Nonabsorbable, synthetic, monofilaments best in this situation). This is the least reactive suture.

Answer 373

- Strong suture. May be used for tendon repair. | - Braided. May be coated with silicone.

Answer 374

- Monofilament or braided (braided is called Flexon) - Strongest suture with longest absorption rate - Used for bone fixation and tendon repair, but may corrode bone at stress points

Answer 375

-Sutures are also classified according to size. They can range from 0-0 (very thick) to 9-0 (extremely thin). -Surgeon’s choice is extremely variable and you usually just work with what you are used to, but here are some safe bets: -Capsule closure: 2-0 or 3-0 Vicryl -Subcutaneous tissue closure: 3-0 or 4-0 Vicryl -Skin: 4-0 Nylon or Prolene -Skin sutures are removed at 10-14 days because at this point the tensile strength of the wound equals the tensile strength of the suture

Answer 376

stainless steel

Answer 377

- Carbon: gives instrument “hardness” - Chromium: chromium oxide layer prevents corrosion of instrument - Tungsten Carbide: extreme “hardness” for grasping surfaces (teeth of needle drivers) - Nickel - Molybdenum

Answer 378

- There are two different series of stainless steel depending on how it is manufactured: - 300 series Austenitic: Implants and internal fixation. Resists corrosion with resilience. - 400 series Martenitic: Cutting instruments. Hardness maintains sharp edges and jaw alignments.

Answer 379

- Most common: 10, 15, 11, 62 on a minihandle - Purpose: Sharp (blade) and blunt (handle) dissection - Cutting edge width: 0.015”

Answer 380

-Most common: Tissue: Metzenbaum, Mayo, Iris, Crown&Collar (Sistrunk) Non Tissue: Suture, Utility, Bandage Purpose dissection

Answer 381

- Most common: Mosquito (Halsted), Kelly, Crile | - Purpose: Grasping and holding

Answer 382

- Most common: 1-2 (Rat tooth), Adson-Brown, Atraumatic (Potts-Smith) - Purpose: Grasping and Holding

Answer 383

-Most Common: Hand Held: Skin Hooks, Senn, Ragnell, Malleable, Army-Navy, Volkmann Rake, Meyerding Self-retaining: Weitlaner, Holzheimer, Heiss -Purpose: Retraction and exposure

Answer 384

- Most Common: Freer, Sayre, Key, Crego, McGlamry, Langenbeck - Purpose: Dissection

Answer 385

- Most Common: Joseph, Maltz, Bell, Parkes | - Purpose: Cutting

Answer 386

- Osteotomes - Chisels - Gauges - Mallets - Bone-Cutting Forceps - Rongeurs - Trephine - Curettes - Bone Handling Clamps - Reduction Forceps (Lewin, Lane, Lowman, Verbrugge) - Needle Holders (Mayo-Heger, Sarot, Ryder, Halsey, Webster) - Suction-Tip (Frazier)

Answer 387

teeth enamel

Answer 388

pneumatic electrc battert

Answer 389

- Advantages: Delivers high power and torque, does not overheat, cheap - Disadvantages: Does not operate at slow speeds, bulky, burdensome, cords prone to contamination - General: -Most commonly driven by compressed nitrogen - Tank pressure > 500 psi - Dynamic instrument pressure: 90-110 psi

Answer 390

- Advantages: Light, quiet, small, good for office use - Disadvantages: Prone to overheating, expensive - General: -Utilizes an alternating current drive

Answer 391

- Advantages: No cords - Disadvantages: Loses power quickly, bulky handling - General: -Utilizes direct current

Answer 392

stryker hall-zimmer microair

Answer 393

Measurement of power and force. Units: Newtons/cm^2 | -Cortical bone requires more torque to cut through than cancellous bone

Answer 394

20,000 rpm

Answer 395

decrease torque | and increase seed

Answer 396

distal end of a saw where the saw blade attaes

Answer 397

one area excursion for a saw blade

Answer 398

One back and forth motion of a saw blade. (Two strokes equal one oscillation).

Answer 399

- Sagittal Saw: Cuts in the same plane as the instrument - Better for longer and deeper cuts - 4° arc of excursion - Blade may be positioned anywhere within a 160-180° arc. - Oscillating Saw: Cuts in plane perpendicular to instrument - 7° arc of excursion - Blade may be positioned anywhere within a 360° circle

Answer 400

- Vary by cutting depth, width, thickness, shape and number of teeth - Shapes: straight (most commonly used), inward flair, outward flair - The angulation of the teeth and NOT the thickness of the blade determine the thickness of a cut. - Blades may contain holes which collect debris, thereby decreasing heat and friction

Answer 401

- K-Wires (Kirshner wire) - Sizes: 0.028”, 0.035”, 0.045”, 0.062” - Threaded vs. Non-threaded. Note that the direction of the driver only matters with threaded wires. - K-Wires provide splintage (stability, but no compression) - Steinman Pins - Sizes: 5/64”-3/16”

Answer 402

- Power Drill Bit Sizes: 1.1, 1.5, 2.0mm - Burrs - Shapes: Round, Barrel, Straight, Straight-tapered - Definitions: -shank vs. shaft vs. head - flute vs. blade - edge angle vs. clearance angle vs. rake angle

Answer 403

- The surgeon’s hands provide 3 functions when operating power instrumentation: - Control of power of the instrument - Control of direction of the instrument - Stability between the instrument and the surgical site

Answer 404

- With a saw or K-wire, always divot perpendicular to the cortex, and then redirect. - The spin of a burr should be parallel to the grain of the cortex or parallel the ridge of bone to be removed

Answer 405

clinically inert, no inflammatory or foreign body response, noncarcinogenic, nonallergenic, structurally stable, capable of sterilization, capable of fabrication in desired forms, serve as a scaffold for new bone growth and gradual biodegradation

Answer 406

``` cellular response (acute) tissue remodeling response infectin potential ```

Answer 407

-Immediately after implantation, implants are covered with a coat of proteins that denature and elicit an inflammatory response. Denatured fibrinogen accumulates neutrophils and macrophages. -Detritic Synovitis: Foreign body reaction to shards of silicone materials in the lymphatic system. -Environmental Stress Cracking: Surface defects on polyetherurethane implants secondary to chronic inflammation. Chronic inflammation results from fragmentation and leads to intracortical lysis and cyst formation

Answer 408

fibrous capsule formation

Answer 409

- Susceptible to S. Aureus and S. Epidermidis infections | - Malignancy and Type III hypersensitivity reactions extremely rare

Answer 410

- PLLA (Polylactic-L-Acid: L is enantiomer) - Degrades to lactic acid via hydrolysis - Retains strength 36 weeks and degrades in 2-3 years - Available in FT 2.0, 2.7, 3.5 and 4.5mm screws - PGA (Polyglycolic Acid) - Degrades to glycolic acid and glycine - Elliptical. Provides compression secondary to shape. - Brittle and rigid - Highest likelihood of FB rxn or complication (<4%) - PDS (Poly-para-dioxanone) - Tapered form swaged on metallic wire. Provides compression secondary to shape. - Flexible and malleabl

Answer 411

-Increased degradation times are good because it decreases the load the body has to clear. -These screws don’t “bite” like metal screws, but swell 2-4% in the first 48 hours. -Advantages: decreased stress shielding, no second operation for removal. -Disadvantages: more expensive than metallic screws, but are cheaper in the long run if you remove >31% of metallic screws in your practice.

Answer 412

- Surgical Stainless Steel - 316LVM (low carbon vacuum remelting) - Iron, 17-25% chrome, 10-14% nickel, 2-4% molybdenium, 1% carbon - Nickel most commonly causes reaction: allergic eczematous dermatitis. - Titanium - Very inert, integrates into surrounding bone, resists corrosion, decreased capsule formation - Addition of 6% aluminum and 4% vanadium increases the strength similar to steel - Nitrogen implantation forms a stable oxide layer - Black metallic wear debris is often seen. No toxicity or malignancy associated with this. - Cobalt Chrome and Alloys - 30% cobalt, 7% chromium, <0.034% moly/carbon - Used in joint replacement prostheses

Answer 413

-Corrosion: breakdown of metallic alloys because of electrochemical interactions within the environment

Answer 414

- 377BC: Hippocrates with wood from a cornel tree - 1904: Codvilla (Italy) used unilateral fixator for limb lengthening - 1951-1991: Ilizarov (Siberia, Russia). Father of modern ex-fix and developer of external ring fixator for WWII vets from old bus parts.

Answer 415

-Distraction performed at proper rate and in the proper area leads to tissue growth similar to hormone-mediated growth at adolescent growth plates. -Too fast: Stretching and traction injuries -Too slow: Bone callus consolidation preventing future distraction -An important principle is that all tissues (bone, skin, muscle, NV structures, etc.) become mitogenically active and grow. They proliferate as opposed to “stretching”. Much of this has to do with the distraction serving as a mechanical stimulus for growth factor release (such as osteoblastic growth factor) and dramatic increases in vascularity

Answer 416

-Stability: increased stability leads to increased osteoblastic activity -Rate: Ideal is 1mm/day in 4 increments -Bone Cut: Best to keep medullary canal and as much periosteum intact as possible. Best technique is a percutaneous subperiosteal corticotomy with a Gigli saw or osteotome/mallet. -Location of Bone Cut: Metaphysis found to be superior to other area

Answer 417

- Avoid and respect neurovascular structures - Allow access to injured area for future fixation - Meet mechanical demands of the patient and the injury

Answer 418

- Colloidal (0-2 weeks): formation of microreticular network - Fibrillar (2 weeks-1 month): collagen organization - Lamellar (1 month-years): formation of compact lamellar tissue and calcification

Answer 419

- Decreased soft tissue dissection - Immobilization of multiple regions - Allows for post-operative adjustment - Skin grafting and wound debridement available - Early ROM and WB

Answer 420

- Complications of Ex-Fix - Pin tract infection vs. irritation - Pain - Cage rage - Non-unions - Fracture - NV injury

Answer 421

-Knowledge of cross-sectional anatomy is essential for the application of external fixation. There are numerous manuals and tests available demonstrating proper pin and wire placement in a given location. -The key is to have solid bone with avoidance of neurovascular structures. -As a general rule, the medial and anterior aspects of the tibia are safe locations.

Answer 422

unilateral circular hybrid fixators taylor spatial frames

Answer 423

- EBI Dynafix and Orthofix - Can be straight (uniplanar) or articulated (multiplanar) - Allow for compression/distraction in a single plane only - Attached to bone via half-pins - Rigidity and stiffness determined by half-pins/bone interface. Want pins spread over a large area. - Weak in the sagittal plane

Answer 424

Multi-latral - Smith&Nephew - Generate compression/distraction in multiple planes - Tensioned wires generate stability; half-pins generate rigidity. - Best if these are located 90° to each other for optimal stability - Can be formulated to allow for immediate WB

Answer 425

- Orthofix, Dynafix, Smith&Nephew, Rancho | - Combination of unilateral and circular fixato

Answer 426

- Smith&Nephew | - Allows for reduction of triplanar complex deformitie

Answer 427

- Limb Lengthening/Distraction - Percutaneous metaphyseal subperiosteal corticotomy with Gigli saw or osteotome/mallet - Apply fixation before corticotomy - Distraction begins 7-14 days after corticotomy at 1mm/day - Angular Deformities - CORA principle (center of rotational angulation) - Double Taylor spatial frame - Dynamization: release of tension from wires and loosening of half-pins to allow bone a period of introductory WB - Fracture - Ligamentotaxis: pulling of fracture fragments into alignment with distraction -Arthrodesis

Answer 428

-Bone is a two component system consisting of minerals (increases the yield and ultimate strength of bone) and collagen (mostly Type II).

Answer 429

-Porosity. Increased porosity leads to increased compressive strength of bone. Cortical bone has <15% porosity and cancellous bone has ~70% porosity. -Strength. Strength is defined as the amount of force a material can handle before failure. Bone can handle a 2% increase in length before failure. Bone is has the greatest strength in compression, followed by tension and is weakest in shear. Strength is affected by collagen fiber orientation, trabecular orientation, age, presence of defects and osteoporosis. -Stiffness. Cortical bone has 5-10 times the stiffness of cancellous bone

Answer 430

-Blood supply to bone comes from two sources. A nutrient artery feeds the endosteal and medullary vessels and supplies the inner 2/3-3/4 of bone. The periosteal vessels supply the outer 1/3 of bone from muscle and tendon attachments. -The amount of vascular disruption following a fracture depends on the force/displacement of the fracture and which vascular systems are disrupted.

Answer 431

inflammation (10%) Reparative/Regeneration (40% Remodeling (70%)

Answer 432

- Hematoma fills the area with fibrin, RBCs, neutrophils, platelets, macrophages, fibroblasts (from PMNs). - Mesenchymal cells from the cambium layer differentiate into osteoblasts and chondrocytes. - Chemotaxis by growth factors (transforming growth factor beta, platelet derived, and macrophage derived)

Answer 433

- Soft callus forms and is replaced by bone. - Cartilage, fibrocartilage, collagen and hydroxyapatite deposition - Cartilage replaced by bone like endochondral ossification

Answer 434

- Callus completely replaced by bone - Vascular network is normalized - Remodels according to Wolff’s Law - Piezoelectric Effect: appearance of electrical potentials within bone in response to the application of an external force - Compression side: electronegative leading to bone production - Tension side: electropositive leading to bone resorption

Answer 435

- Direct Osseous Repair (Primary Intention, Direct Healing) - No callus formation; no motion - Cutting cone: Osteoclasts in the front, osteoblasts in the back. Travels across the fx line (Schenk and Willinegger). - Gap Healing: Bone deposition at 90° to the orientation of bone fragments - Indirect Osseous Repair - Callus formation

Answer 436

1. Substrate/Lag/Inflammatory Stage (Days 1-4) - Inflammation characterized by edema/erythema/calor/dolor - PMNs start out dominating, but are eventually taken over by macrophages 2. Proliferative/Repair Phase (Days 3-21) - Collagen proliferation and macrophages - Myofibroblasts also begin working 3. Remodeling/Maturation Phase (Day 21+)

Answer 437

``` “In the area of the patient’s presenting complaint I see a (mild, moderate, or severe) hallux abductovalgus deformity at the level of the metatarsal-phalangeal joint as defined by a (mildly, moderately, or severely) increased intermetatarsal angle, (mildly, moderately, or severely) increased hallux abductus angle, and approximate tibial sesamoid position of (1-7). The PASA and DASA of this joint appear (within normal limits or deviated). There (does or does not) appear to be a hallux interphalangeus deformity as defined by the (increased or normal) hallux interphalangeus angle. The overall length of the first metatarsal appears (normal, shortened, or long) compared to the remainder of the lesser metatarsal parabola on the AP view. On the lateral view the first metatarsal appears (dorsiflexed, plantarflexed, or normal) compared to the second metatarsal using Seiberg’s index. There (is or is not) an underlying metatarsus adductus as defined by the metatarsus adductus and Engle’s angles. Generally, the rearfoot appears (rectus, pronated, or supinated) as defined by…” ```

Answer 438

“Consistent with the patient’s presenting complaint we see a (mild, moderate, or severe) pes planovalgus deformity. In the sagittal plane I see a (decreased or increased) calcaneal inclination angle, talar declination angle, talar-calcaneal angle, first metatarsal inclination angle, Meary’s angle, and medial column fault on the lateral view. I would also evaluate the patient for equinus using the Silfverskiold test to determine a sagittal plane deformity. In the transverse plane I see a (decreased or increased) talar-calcaneal angle, cuboid abduction angle, talar head coverage, talar-first metatarsal angle, metatarsus adductus angle on the AP view. In the frontal plane we can see the Cyma Line is (anteriorly displaced, posteriorly displaced or normal) on the lateral view, and that the subtalar joint alignment, ankle joint alignment and calcaneal position are (normal or abnormal) on the long leg calcaneal axial views.”

Answer 439

``` Now that you have defined the deformity on your own terms, you can now suggest how to fix it using the same tools. “I would consider performing a (Gastroc recession, TAL, Cotton osteotomy, medial column arthrodesis, etc.) to correct for the sagittal plane deformity, a (Evans osteotomy, CC joint distraction arthrodesis, etc.) to correct for the transverse plane deformity, and a (medial calcaneal slide, STJ implant, etc.) to correct for the frontal plane deformity. ```

Answer 440

- CC: Pt can complain of generalized “corns, calluses and hammertoes.” - HPI: -Nature: “Sharp, aching and/or sore” type pain. May have a “tired feeling” in the feet. - Location: Usually dorsal PIPJ/DIPJ of the toes or submetatarsal - Course: Progressive onset and course. - Aggravating factors: WB, shoe gear (especially tight shoes) - Alleviating factors: NWB, wide shoebox, sandals - PMH/PSH/Meds/Allergies/SH/FH/ROS: Usually non-contributory

Answer 441

-Derm: -Hyperkeratotic lesions can be seen submetatarsal, dorsal PIPJ or DIPJ of the lesser digits, distal tuft of the lesser digits, or interdigitally. All can have erythema, calor and associated bursitis. -5th digit is usually dorsolateral at the PIPJ, DIPJ or lateral nail fold (Lister’s corn). Hyperkeratotic lesion of the adjuvant 4th interspace may also be present (heloma molle).

Answer 442

-Positive Coughlin test: Vertical shift of >50% of the proximal phalanx base on the met head. Also called the “draw sign” or Lachman’s test. -Kelikian push-up test: Differentiate between a soft-tissue and osseous deformity -Specific to the 5th digit: -Toe usually has a unique triplanar deformity (dorsiflexion, adduction and varus). -Bunionette, splay foot and equinus may be present -The 5th digit is in the most susceptible position in terms of a muscular imbalance deformity because the FDL has such an oblique pull on the 5th digit as opposed to the relatively axial pull of the other digits.

Answer 443

gun barrel sign

Answer 444

-Hammertoe: Extension at MPJ level; flexion at PIPJ level, neutral/extended DIPJ -Mallet toe: Neutral at MPJ and PIPJ level; flexion at DIPJ level -Claw toe: Extension at MPJ level; flexion at PIPJ and DIPJ level -Curly toe: Claw/hammertoe deformity with an additional frontal plane component -Digitus Adductus: Digital deformity with adduction in the transverse plane -Digitus Abductus: Digital deformity with abduction in the transverse plane -Heloma Molle: Generally occurs in the 4th interspace with a curly toe deformity of the 5th digit. Using this example, the head of the proximal phalanx of the 5th digit abuts the base of the proximal phalanx of the 4th digit causing a hyperkeratotic lesion in the proximal 4th interspace.

Answer 445

During weight-bearing, the toes cannot function in propulsive gait to aid in load transfer if the most distal segment is not stabilized. The distal phalanx is stabilized by the long flexor tendons holding it solidly against the weight-bearing surface. With the distal phalanx stabilized, the short flexor tendon can hold the middle phalanx against the weight-bearing surface. With the middle phalanx stabilized, the lumbrical muscles hold the proximal phalanx against the ground. The lumbrical muscles must work against the extensor tendon complex, but this complex is usually not actively firing to extend the MPJ during propulsion. The interosseous muscles also stabilize the proximal phalanx in the transverse plane. When the proximal phalanx has been effectively stabilized against the weight-bearing surface, the head of the metatarsal can effectively move through its range of motion and transfer load across the metatarsal parabola. Any disruption in the stabilization process will lead to abnormal biomechanics and deformity

Answer 446

-Most common origin of hammertoe deformity -Occurs when the PT muscle is unable to effectively resupinate the midtarsal and subtalar joints at the beginning of propulsion. To compensate, the FHL and FDL fire earlier, longer and with greater force to resupinate the foot. This puts too much force on the distal and middle phalanges causing the toe to “buckle” in a dorsiflexed position at the MPJ. This retrograde buckling puts the PIPJ in a vulnerable dorsal position and also pushes the metatarsal head plantarly.

Answer 447

-Occurs when the triceps surae muscle group is unable to effectively plantarflex the foot during propulsion for whatever reason. To compensate, the muscles of the deep posterior compartment (PT, FHL, and FDL) again fire earlier, longer and with greater force leading to the same type of deformity

Answer 448

-Can occur in two ways -One way is when the TA is unable to dorsiflex the foot through the swing phase. In this case the EDL and EHL fire earlier, longer and with greater force than normal and are actually actively extending the MPJ. This easily overpowers the lumbricals and leads to retrograde buckling. -The other way is in a situation with anterior cavus where the EDL is actually at a mechanical advantage over the lumbricals. Passive stretch of the EDL, rather than active contraction, overpowers the lumbricals and leads to deformity

Answer 449

-Do nothing: Digital deformities are not a life-threatening condition and can be ignored if the patient is willing to put up with it. -Palliative care: Periodic sharp debridement of hyperkeratotic lesions -Splints/Supports: -Metatarsal sling pads -Silicone devices -Toe crests -Orthotics: -Cut-outs of high pressure areas -Metatarsal pads to elevate the metatarsal heads -Correction of the underlying deformity

Answer 450

- HEECAT - Head arthroplasty: Post procedure (1882) - Extensor hood and PIPJ capsule release - Extensor tendon lengthening - Capsulotomy (MPJ) - Arthrodesis (PIPJ) - Tendon transfer (flexor longus tendon transfer to function in MPJ plantarflexion

Answer 451

-Done proximal to MPJ level with a Z-lengthening

Answer 452

- Of the PIPJ and MPJ - Remember the “J” maneuver for release of the collateral ligaments - Extensor hood release is also usually performed - Some use the McGlamry elevator in this step to free plantar attachments

Answer 453

- Post procedure 1882 | - Resection of the head of the proximal phalanx at the surgical neck

Answer 454

- Fusion of the PIPJ using a variety of techniques: table-top, V, peg-in-hole, etc. - Fusion maintained with K-wire crossing the MPJ extending into the distal 1/3 of the metatarsal

Answer 455

-Transfer of the FDL tendon dorsally to act as a more effective plantarflexor of the proximal phalanx -Girdlestone-Taylor technique: Tendon is bisected, crossed and sutured on the dorsal aspect. -Kuwada/Dockery technique: Tendon is re-routed through a distal drill hole -Schuberth technique: Tendon is transferred through a proximal drill hole

Answer 456

- Soft tissue fusion of one digit to a normal adjacent digit to help “bring it down” - Interposing skin is removed and the digits are sutured togethe

Answer 457

-It is possible to alter your skin incision to incorporate a derotational element to your skin closure. While the osseous work can be accomplished using a longitudinal or lazy “s” incision (proximal medial to distal lateral), those are really best for uniplanar deformities. 5th digit HT is usually a triplanar deformity. - Two semi-elliptical incisions directed proximal lateral to distal medial. - The more oblique the incision is, the greater transverse plane correction. - The more longitudinal the incision is, the greater the frontal plane correction.

Answer 458

- CC: Pt presents complaining of “pain in the ball of my foot.” - HPI: -Nature: Generalized pain (aching, sharp, sore, etc.) - Location: Submetatarsal. Can usually be localized to an exact metatarsal. - Course: Gradual and progressive onset. “Has bothered me for years.” - Aggravating factors: WB for long periods, shoe gear, etc. - PMH/PSH/Meds/All/SH/FH/ROS: Usually non-contributory

Answer 459

``` Derm: -Diffuse or focal hyperkeratotic lesions submetatarsal Vasc/Neuro: Usually non-contributory Ortho: -Many of the same signs/symptoms as HT digital deformity. HT often present. -Anterior displacement of the fat pad -Hypermobility of the first ray -Anterior Cavus foot type -Hypermobility of the fifth ray -Equinus ``` Objective: Imaging - Plain film radiograph: - Look for irregularities of the metatarsal parabola - Look for excessively plantarflexed or dorsiflexed position on lateral/sesamoid axial views

Answer 460

-Retrograde force from hammertoes. Please see AJM Sheet: Digital Deformities. -An excessively long and/or plantarflexed metatarsal leads to increased load bearing under that particular metatarsal. -An excessively short and/or dorsiflexed metatarsal can lead to increased load bearing on the adjacent metatarsals. -Hypermobility of the first ray leads to increased load bearing under at least the second metatarsal. -Hypermobility of the fifth ray leads to increased load bearing under at least the fourth metatarsal. -Anterior cavus and equinus deformities lead to increased pressures across the forefoot. -Before a surgical option is considered, it is extremely important to understand where the increased load is coming from. The goal of treatment should be to restore a normal parabola and weight-bearing function to the foot. Failure to correct the underlying deformity will dramatically increase the rate of recurrence and transfer lesions.

Answer 461

- Do nothing: Lesser metatarsal deformities are not a life-threatening condition. - Palliative care: Periodic sharp debridement of hyperkeratotic lesions - Splints/Supports: -Metatarsal sling pads - Toe crests - Silicone devices - Orthotics: - Cut-outs of high pressure areas - Metatarsal pads to elevate the metatarsal heads - Correction of the underlying deformity

Answer 462

distal met proc Met shaft proc met base proc

Answer 463

-Duvries: plantar condylectomy on both sides of the MPJ -Jacoby: “V” shaped cut in the metatarsal neck to allow for dorsiflexion of the head -Chevron: “V” shaped cut similar to a Jacoby, but with removal of a wedge of bone to obtain metatarsal shortening as well. -Dorsiflexory wedge osteotomy: similar to a Watermann of the first metatarsal -Weil: Distal dorsal to proximal plantar oblique cut to allow for distal metatarsal dorsiflexion and shortening. Can be made in several planes to obtain desired dorsiflexory/shortening effects. -Osteoclasis: Through and through cut through the metatarsal neck allowing the distal head to find its own plane.

Answer 464

- Cylindrical shortening | - Giannestras step-down procedure: Z-shaped cut which can allow for shortening and distal dorsiflexion.

Answer 465

- Dorsiflexory wedge: (1mm of proximal dorsal shortening equivalent to ~10 degrees of dorsiflexion) - Buckholtz: Oblique dorsiflexory wedge which allows for insertion of a 2.7mm cortical screw

Answer 466

floating toe recurrence transfer lesions

Answer 467

-[Derner and Meyr. Complications and Salvage of Elective Central Metatarsal Osteotomies. Clinics Pod Med Surg. Jan 2009

Answer 468

-4-5 Intermetatarsal Angle > 9 degrees (Normal is 6.47 degrees per Fallat and Buckholtz) -Lateral Deviation Angle > 8 degrees (Normal is 2.64 degrees per Fallat and Buckholtz) -[Fallat LM, Buckholtz J. J Am Podiatry Assoc. 1980 Dec; 70(12): 597-603.] -Splay Foot Deformity -Plantarflexed 5th metatarsal position -Structural changes to 5th metatarsal head

Answer 469

-Numerous authors have chimed in on the etiology of the 5 th Metatarsal Deformity: -Davies: incomplete development of deep transverse metatarsal ligament -Gray: malinsertion of adductor hallucis muscle -Lelievre: forefoot splay -Yancey: congenital bowing of metatarsal shaft -Root: abnormal STJ pronation -CMINT, etc, etc, etc

Answer 470

- Do nothing: 5th metatarsal deformities are not a life-threatening condition. - Palliative care: Periodic sharp debridement of hyperkeratotic lesions - Splints/Supports: -Shoe gear modification with large toe box - Derotational tapings - Orthotics: -Cut-outs of high pressure areas - Metatarsal pads to elevate the metatarsal heads - Correction of the underlying deformity

Answer 471

-Exostectomy: Removal of prominent lateral eminence from 5thmet head -Arthroplasty: Removal of part/whole of 5thmet head -Distal Metatarsal Osteotomies: -Reverse Hohmann -Reverse Wilson -Reverse Austin -Crawford: “L” shaped osteotomy allows for insertion of cortical screws -LODO (Long Oblique Distal Osteotomy): similar to Crawford but simply oblique -Read [London BP, Stern SF, et al. Long oblique distal osteotomy of the fifth metatarsal for correction of tailor's bunion: a retrospective review. J Foot Ankle Surg. 2003 Jan-Feb;42(1):36-42.] Especially if externing at Inova! -Medially-based wedge -Proximal Osteotomies: -Transverse cuts -Oblique cuts -Medially based wedges

Prism Flashcards

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