fracture fixation

Question 1

Causes of Fracture

Answer 1

External forces
* Relatively minor to Violent
* Repetitive stresses (fatigue fracture)…rare
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Internal forces
* Less frequent
* Avulsion of tendons…

Question 2

Fracture Care

Answer 2

• Address life threatening injuries
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  Airway/Breathing
• Chest injuries = 50%
  > Lung contusions 66%
  > Pneumothorax 30%
  > Diaphragmatic hernia 3%
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  Cardiovascular
• Cardiovascular shock
• VPC

Question 3

Minimum Database

Answer 3

PCV, TP, BUN (QAT’s)
* CBC/Chemistry to follow
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CHEST RADIOGRAPHS
* All violent trauma
* All unknown trauma
* May need to be repeated >24h
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Abdominal Radiographs / Ultrasound
* Suspicion of abdominal organ injury
* Bladder…

Question 4

Pre-operative Fracture Care

Answer 4

• Analgesia
• NSAID (if no contraindications)
• Morphinic
  > Methadone, hydromorphone, oxymorphone, buprenorphine,…
  > Continue until post op
  > May (should) require hospitalization
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• Antibiotics: Not needed unless open!
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  Stabilize the fracture if applicable
• Splint (Distal fractures)
• (Robert Jones)
• Cage rest until repair (All fractures)

Question 5

Fracture Care
- timing of repair
- delays?

Answer 5

• As soon as the animal is stable
• Generally within 1 to 3 days
  > Decreases morbidity
  > Decreases mortality
  > Decreases cost
  > Improves well being
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  Longer delays increases complications
• Increased difficulty of procedure
• Particularly young animals
• Do not let the client unnecessarily delay!

Question 6

Open Fractures - what we need to do ASAP

Answer 6

• Prevent further contamination
• Provide antibiotic coverage ASAP
  > Broad spectrum IV (cefazolin or ampi/baytril)
  > Continue until definitive closure
• Wound management ASAP
  > Same as other wounds
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• Provide temporary stabilization
• Repair sooner than later

Question 7

Fracture Classification
- what info do we need

Answer 7

1. Bone involved
2. location within the bone
3. Complexity of the fracture
4. configuration
5. Closed / Open
6. Displacement

Question 8

simple vs comminuted fracture

Answer 8

Simple
* 1 Fracture line
* Low energy trauma
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Comminuted
* multiple fracture lines (several fragments)
* high energy trauma

Question 9

possible fracture configurations

Answer 9

• Applies to simple fractures
• Does not apply to comminuted Fracture
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  1. Transverse
  2. Oblique
• Short (< 2X diameter)
• Long (> 2X diameter)
  3. Spiral
  4. With butterfly fragment

Question 10

transverse fracture
- what is it, good repair method
- healing properties

Answer 10

Roughly perpendicular
* Good for a bone plate
> Compression
* Bone able to provide support when healing

Question 11

Oblique Fracture
- short vs long categorization
- how we treat

Answer 11

Short Oblique
* Approximately 30 deg
* Treated like transverse
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Long Oblique
* Approximately 60 deg
* Fx >2x bone Ø
* Maybe treated with pin and wire

Question 12

spiral fracture
- common? how it arises
- how to treat

Answer 12

Easiest fracture to get
* Often dog playing… low energy
* Result from torsion of bone
* Treated like long oblique fractures

Question 13

Butterfly Fragment
- what is this
- fixation must do what
- how to fix

Answer 13

• Results from bending forces
• Technically a comminuted fracture
  > Fracture fixation must resist bending forces > Plate/rod, Interlocking nail…

Question 14

Closed / Open
- what do we look for?

Answer 14

Closed / Open
* Skin damage
* Presence of gas in soft tissues…
* Cannot always tell on radiographs
> Always examine the leg!

Question 15

Displacement of a fracture
- how do we describe it?

Answer 15

• Describe the position of the distal fragment relative to parent bone
• Always described in terms of the distal fragment

Question 16

Salter Harris Classification
- for what?
- prognosis for different areas?

Answer 16

Fractures of the growth plate have a different classification
* Loosely linked to prognosis
* Based on
> Likelihood damage to specific zones
> Articular damage
* But! Not as accurate as hoped
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- Damage of the epiphysis is likely articular
- Proliferative zone: Damage in this zone leads to irreversible damage
- hypertrophic zone: This zone is the most fragile but can recover
- trabecular bone: Damage in this zone is easily recoverable

Question 17

Salter Harris Classification
- prognosis for growth?
- articular Fx outcomes
- what type will definitely cease growth

Answer 17

Naturally occurring fractures involved all the zones
* Prognosis for growth is always guarded
* Articular Fx lead to additional DJD
* Type V Fx leads to complete/partial cessation of growth

Question 18

Goals of fracture fixation:

Answer 18

Return to full function
* Bone reconstruction
* Preservation of the blood supply
* Stable fixation
* Early active, pain free movement and full weight bearing
> (Activity must ALWAYS be restricted to avoid failure)