What is bone graft?
A biomaterial with either osteoConductive, osteoInductive, and/or osteoGenic properties.
What are the functions of bone graft?
What is Autograft?
What are the advantages/ disadvantages?
Autograft:
Bone graft transferred from one body site to another site in the same patient.
In the form of cortical, cancellous, or corticocancellous.
Can be vascular or nonvascular.
Advantages:
Disadvantages:
Donor site morbidity, may not be sufficient
What are the types of bone graft that can be obtained from anterior iliac crest harvesting?
Cortical and cancellous BGs.
Bicortical or tricortical BGs.
Bone marrow aspirates.
How to perform anterior iliac bone graft harvesting?
Supine, sandbag under ipsilateral buttock to accentuate the ASIS, instrumentation table and scrub nurse are positioned at the ipsilateral site, surgeon on ipsilateral side, prophylactic antibiotics, time-out.
Locate and mark the ASIS. Palpate the widest part of the iliac crest forming the iliac tubercle (about 5–6 cm posterior to the ASIS).
Starting 2–3 cm posterior to the ASIS (to avoid LFCN, prevent avulsion fracture), make a line 8 cm long parallel to the iliac crest, centered over the iliac tubercle. make incision 1 cm more laterally (inferiorly) or medially (superiorly) from the iliac crest to avoid a painful scar on the ridge of the iliac crest.
2. Dissection
Retract the skin to reach the fascia layer. Using the cutting diathermy, split fascia longitudinally Dissect down to the bone, creating a full thickness flap. Plane is between tensor fascia lata laterally and external and transverse abdominal muscles medially exposing the iliac crest. Sharply incise the periosteum to expose the iliac crest. Then release tensor fascia latae to expose the outer table, reflect the iliacus off to expose the inner table.
3. Harvesting at site
a) Tricortical BG
2 parallel osteotomy cuts between the required lenght size BG required, 1 osteotomy cut perpendicular to iliac tubercle with curved osteotome (up to 5 cm).
b) Bicortical BG
Osteotome a superior cut mid-crestally, then 2 vertical cuts on either side of the superior cut, followed by an inferior horizontal cut with curved osteotome (up to 5 cm).
c) Cancellous BG
Trapdoor method.
Incise periosteum on outer crest, make horizontal cut in the iliac crest with a straight osteotome, approximately 2 cm below curve of the crest, keeping the inner table intact, collect using curette or gouge, hinge crest back like a trapdoor.
Vertical section of the ilium showing the trapdoor method of harvesting bone graft. The periosteal and fascial attachments of the iliacus and abdominal wall muscles remain intact on the inner edge of the horizontal cut through the iliac crest, thus allowing the crest to be “hinged back” like a trapdoor.
Attached: Tricortical bone harvesting
What are the complications of anterior iliac crest harvesting?
Donor site pain, superficial cutaneous sensory nerve impairment (numbness, parasthesia, burning sensation at anterolateral aspect of the thigh but NO motor weakness or wasting/no reduced knee jerk reflexes - (damage to LFCN), seroma, haematoma, infection.
What are the structures at risk in posterior iliac crest harvesting?
1) Superior cluneal nerves - cross crest 8cm lateral to PSIS -> low back pain, numbness upper 2/3 buttocks
2) Middle cluneal nerves -> numbness medial aspect of buttocks
3) Greater sciatic notch - 6-8cm inferior to posterior crest, contains:
(i) sciatic nerve,
(ii) superior gluteal nerve (gluteus medius, minimus to abduct hip) & inferior gluteal nerve (gluteus maximus to extend hip),
(iii) superior gluteal vessels
4) Posterior ligamentous complex of SI joint - medial to PSIS -> SI joint disruption -> pain, instability
*If a Cobb elevator is directed caudally while stripping the periosteum over the iliac wing, it will encounter the sciatic notch. Although this puts the sciatic nerve at risk, the first structure encountered is the superior gluteal artery. Because it is tethered at the superior edge of the notch, it is very vulnerable to injury and can then retract inside the pelvis, making it difficult to obtain hemostasis. The inferior gluteal artery exits the sciatic notch below the piriformis and is more protected. The cluneal nerves are at risk only if the incision extends too anteriorly, and the sacroiliac joint can be entered while harvesting the graft.
Define Holstein-Lewis fracture? How does it occur
The Holstein-Lewis fracture describes a type of humeral fracture
How will you manage an open Holstein-Lewis fracture?
When will you explore radial nerve in radial nerve palsy following fracture of humerus?
Acute setting
Delayed setting
by 6 months, when no signs of nerve recovery by clinical or electrodiagnostic assessments.
Nerve repair
During wound debridement and ORIF of an open humerus fracture, you encountered this. How will you manage this?
Intra-operative finding is of a transected radial nerve following open fracture of the humerus in context of high-energy motorvehicle accident. (Have to highlight that high energy injury, has high risk of neurovascular injury, also need TRO vascular injury which is more important for limb salvage)
After performing thorough wound debridement and plating of the humerus fracture (if vascular injury present, neuroraphy is after), I will proceed to addressing the transected radial nerve.
Using loupe or microscopic magnification, I will identify the proximal and distal portions of the transected radial nerve, using Jewellers forceps to handle these portions with care by only manipulating/holding the epineural layer.
** Primary repair can be done with elbow in flexion but this position is maintained for 3 weeks after surgery and subequently elbow is extended 30 deg/week untill full extension is obtained.
Source from: orthobullet, Miller
What are the principles of nerve transfer?
5) Important denervated recipient
6) Tension-free coaptation through full range of motion
7) Section donor nerve distally, section recipient nerve proximally (=> to obtain tension-free coaptation)
Length of nerve graft:
- 10-20% longer than gap to account for shrinking of graft as result of elastic recoil
How to overcome nerve gap?
For large nerve gaps, do
Direct (end-to-end) (tension-free) repair are reserved for small nerve gaps.
Advantages of Direct Nerve Repair over Nerve Grafting?
Nerve regeneration across nerve grafts not as effective as direct end-to-end repair because:
1) Axonal sprouts must cross two suture lines and the entire length of the interposed graft
2) Graft material does not produce as much biochemical support in the form of tropic and trophic factors to assist the regenerative process
3) Anatomical alignment of donor and recipient nerve tissue may be dissimilar, which may make it difficult to align similar fascicular patterns between nerve stumps
4) Survival of the graft very much depends on its ability to be vascularised by the local blood supply - in cases in which the vascular bed is poor, a section of nerve with its own blood supply, a vascularised nerve graft, may be indicated.
Options for nerve grafting?
Options of nerve graft:
3) Muscle or synthetic conduit (nerve tube made of collagen type 1, polyglycolic acid)
- gaps <3cm
What is neurotisation?
Neurotisation is transfer of a functioning, but less important nerve to a non-functioning nerve to reinnervate a more important motor or sensory territory.
Name donors for autologous nerve graft?
Donors for autologous nerve graft:
- sensory nerves
example:
Sural nerve
Medial or lateral antebrachial cutaneous nerves
Superficial radial nerve (can cause morbidity)
Dorsal cutaneous branch of ulnar nerve
What are the principles of primary nerve repair?
1) Preparation of nerve end
- zone of injury resected until healthy tissue & normal fascicles (‘mushrooming’ of fascicles seen)
- well-vascularised wound bed, minimal contamination
- skeletal stability, soft tissue coverage
2) Approximation
- tension-free
- end-to-end
- proper rotational alignment of fascicles (aided by aligned epineural blood vessels)
- epineural repair
- microsurgical expertise & instruments available, suture 9/0 or 10/0,
- other alternative: end-to-side, group fascicular repair
3) Maintenance of nerve repair
- immobilisation post-op.
72 y. male, right hand dominant, fell from standing position onto left wrist. Following that, had immediate pain and unable to use left hand without discomfort. No other areas of pain, no head trauma, no loss of consciousness. Examination showed obvious wrist deformity and swelling with tenderness to palpation and intact neurovascular- specifically the medial nerve.
Case from Orthobullet Case Study
I would like to order other plain radiographs to assess the entire lenght of radius and ulnar and elbow in AP/Lat to make sure there are no other fractures +/- dislocation present.
at ED: After ensuring no open wounds at fracture site and no neurovascular injury is present, I would attempt a CMR of the fracture with patient under conscious sedation and apply a above elbow POP with 3 point fixation to stabilise the reduction, reassess fracture reduction with plain radiographs of the wrist (study fracture pattern more clearly, any SL ligament injury) as well as neurovascular status of the patient following reduction.
Why do CMR?
Overall, this is an unstable fracture pattern with potential for displacement once soft tissue swelling subsides. I would counsel my patient for surgery- open reduction and internal fixation.
Unstable fracture pattern with potential for displacement once soft tissue swelling subsides, displaced fracture leads to malunion with limited range of motion of the wrist.
as oppose to cast wearing:
b) What kind of surgery?
ORIF, incision lenght, implant made of titanium plate and screws, stable construct, can begin range of motion of the wrist, elbow and fingers (versus if in cast), fracture will take average 12 months to unite, implant will remain in body even after fracture heals and only will be removed after 1.5 years in the event of soft tissue irritation or earlier if there is infection.
+/- median nerve decompression, if presence of median nerve compression following CMR.
c) Potential risk
immediate: median nerve injury, radial artery injury, SSI (especially in patients with Diabetes).
later: delayed wound healing, delayed union, non-union, FPL and extensor tendon attrition and rupture.
Healing of fractures in diabetic patients is prolonged by 87% [80] and has a 3.4 fold higher risk of complications including delayed union, non-union, redislocation or pseudoarthrosis [81, 82]. Clinical studies in humans indicate that diabetes delays fracture healing [82].
Deltopectoral approach
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Deltopectoral approach
*
Deltopectoral approach
Atypical femoral fractures
2. Prolonged use of bisphosphonates
Bisphosphonates inhibit osteoclasts and decrease bone remodelling that may lead to accumulation of microdamage and stress fracture in the femoral shaft (below the lesser trochanter and proximal to the supracondylar flare).
4.
i) Evaluation of segmental fracture of same femur and fracture of contralateral femur
Ensure no other areas of fractures- incomplete, impending fractures at same limb and contralateral side.
ii) Evaluation of bone metabolism
Bone biomarkers: Ca, Vit D, iPTH, bone turnover markers
iii) Medical management:
Stop bisphosphonates (antiresorptive), change to teriparatide (anabolic agent) and supplemented with Calcium and Vit D.
iv) Surgical management:
Avoid/limiting weight bearing for incomplete femoral fracture.
iv) Intramedullary nailing (cephalomedullary type- covers for femoral neck)- for complete and incomplete AFF.
KIV long plate fixation in cases of very bowed or narrow femur.
→ thigh/groin pain - do bone scan/MRI - abnormal and normal requires clinical and imaging evaluation.
→ no pain - clinical and xray / DXA observation.
References:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4878072/
https://ota.org/sites/files/2021-06/Geriatric%20Fx%202%20Atypical%20Femur%20Fractures.pdf
Pathological fracture: Metastases
56 year old, history of fall in bathroom, unable to ambulate thereafter.
This is the AP and lateral projection of the index patient’s left hip, showing a spiral/long oblique subtrochanteric femur fracture with mottled appearance proximal and distal to the fracture line.
This is most likely a pathological fracture of the left subtrochanteric femur.
ATLS
Secondary survey - Ensure no other areas of injuries such as head, spine, other limbs.
Take history and examination from patient
History - current or previous Hx of cancer or infection, any lumbs or bumps, any other symptoms indicating primary malignancy (haematuria, haematochezia, dark coloured stools, per vaginal bleeing, haemoptysis, altered bowel habits), constitutional symptoms (LOA, LOW).
Xray:
Full length view of the left LL with hip and knee joint in view.
If also complaining of pain at right LL, the same views required.
Blood Ix: FBC, LFT, electrolytes like calcium, ALP, tumour markers for breast, endocrine, ovarian, bowel Cas, electrophoresis ofr M band.
Imaging Ix: CT TAP for primary and metastases.
Multidisciplinary team approach, in which will involve
if lung mets present - respiratory physicians/ thoracic surgeons.
to discuss
Orthopaedic management
Aim for operative intervention to reduce and stabilise fracture because
a) Regain patient’s mobility - to reduce risk of DVT/PE, sacral sore, pneumonia.
b) Improve fracture healing - pathological fracture has prolonged/non-healing, added by the fact it is subtroch region with precarious blood supply.
c) Ease nursing care - once fracture fragments are stabilised as one unit, reduced pain, ease turning of patient.
Aim during operation is to get
A) Lenght, Allignment, Rotation with a Stable fixation.
Choice of fixation is cephalomedullary nailing spanning the whole femur.
If contralateral femur also has mottled appearance with no fracture, will score Mirel, consider prophylactic cephalomedullary nailing spanning the whole femur as well.
https://sci-hub.se/https://doi.org/10.1016/S0020-1383(03)00101-3
If primary tumour is breast or prostate (male) with better prognosis for patient, will consider an endoprosthesis replacement with a long stem.
B) Bone biopsy for HPE