Femoral Shaft Fracture — ABOS Oral Boards Preparation
What examiners expect and how to prepare
Clinical Scenario
A 28-year-old right-hand-dominant male construction worker is brought to the trauma bay after a motorcycle collision at approximately 40 mph. He was helmeted and reports pain in his right thigh. He is hemodynamically stable after 2 liters of crystalloid. ATLS primary survey reveals no other injuries. On secondary survey, the right thigh is swollen and deformed with shortening. The skin is intact. He has palpable dorsalis pedis and posterior tibial pulses. Sensation is intact in all distributions. The knee ligaments cannot be assessed due to thigh pain, but there is no knee effusion.
AP and lateral radiographs of the right femur reveal a comminuted midshaft femoral fracture (AO 32-B2) with approximately 3 cm of shortening. The ipsilateral hip and knee films show no associated fractures. A CT of the femoral neck was obtained given the high-energy mechanism and shows no occult femoral neck fracture.
You performed antegrade intramedoral nailing through a piriformis entry point using a reamed, statically locked nail. Intraoperative fluoroscopy confirmed anatomic length and rotation restoration. The patient was made weight-bearing as tolerated immediately post-operatively and discharged on hospital day two with outpatient physical therapy.
What Examiners Look For
- Data gathering: Mechanism and energy level matter — ATLS principles, associated injury screening, and hemodynamic status come before fracture details.
- Diagnosis: Why did you get a CT of the femoral neck? Discuss the incidence of ipsilateral femoral neck fractures and why they are frequently missed.
- Treatment plan: Why reamed antegrade nailing? What are the alternatives (retrograde, plating) and when would you choose them?
- Technical skill: Entry point selection — piriformis versus trochanteric — and the rationale. How do you assess and restore rotation?
- Indications: What is the role of temporary external fixation in polytrauma? When is damage control orthopedics appropriate?
- Complications: What if the fracture is not healed at 6 months? Describe your approach to femoral shaft nonunion including exchange nailing.
- Applied knowledge: Discuss the timing of definitive fixation — early total care versus damage control — and how you decide.
Common Pitfalls
- Missing an ipsilateral femoral neck fracture — this is the most commonly tested associated injury and must be ruled out before nailing.
- Not discussing rotation assessment intraoperatively — this is a common source of malreduction.
- Forgetting compartment syndrome as a potential complication of femoral shaft fractures.
- Overcomplicating the surgical description — examiners want a clean, stepwise answer.
- Not knowing your nonunion algorithm — exchange nailing, augmentation plating, or bone grafting.
Key Classifications
Free — takes 3 minutes