Compartment Syndrome — ABOS Oral Boards Preparation
What examiners expect and how to prepare
Clinical Scenario
A 19-year-old right-hand-dominant male college soccer player presents to the emergency department 4 hours after sustaining a closed tibial shaft fracture during a game. He was initially splinted at an urgent care center and sent to your facility. He reports escalating pain in his right leg that is not controlled by IV morphine. He rates his pain 9/10. On exam, the right leg is in a well-padded short leg splint. After splint removal, the anterior compartment is tense and firm. He has severe pain with passive extension of the toes — particularly the great toe. Active dorsiflexion is present but weak and painful. The lateral and deep posterior compartments are firm. Sensation is diminished in the first web space (deep peroneal nerve distribution). Pedal pulses are palpable and 2+.
Radiographs obtained at the outside facility show a minimally displaced transverse tibial shaft fracture at the junction of the middle and distal thirds. The fibula is intact.
You diagnosed acute compartment syndrome based on clinical findings and performed emergent four-compartment fasciotomy through a two-incision technique. Intraoperatively, all four compartments were decompressed with bulging muscle noted in the anterior and lateral compartments. Muscle appeared viable with contractility on stimulation. The tibial fracture was stabilized with an intramedullary nail through the same anesthetic. Fasciotomy wounds were managed with vessel loops and wound VAC, with delayed primary closure performed at 48 hours once swelling subsided.
What Examiners Look For
- Data gathering: The clinical presentation drives this diagnosis — pain out of proportion, pain with passive stretch, and a tense compartment. Can you present the classic findings in order of reliability?
- Diagnosis: When do you measure compartment pressures versus operating on clinical suspicion alone? What is the delta-P threshold and how is it calculated?
- Treatment plan: Describe the two-incision technique — where do you place your incisions, which compartments does each access, and what are the critical structures at risk?
- Technical skill: How do you confirm complete fascial release in all four compartments? What are the boundaries of each compartment?
- Complications: What if you perform fasciotomy and the muscle is dead? How do you handle non-viable muscle? What about missed compartment syndrome presenting at 24 hours?
- Ethics: Discuss the medicolegal implications — compartment syndrome is one of the most litigated complications in orthopedics.
Common Pitfalls
- Waiting for a loss of pulse to diagnose compartment syndrome — this is a late finding, and waiting for it means tissue death.
- Relying solely on compartment pressure measurements in a clinically obvious presentation — clinical diagnosis is sufficient.
- Not knowing the four compartments of the leg and their contents — this is foundational anatomy the examiner expects instantly.
- Performing a single-incision fasciotomy and failing to decompress the deep posterior compartment.
- Not discussing the obtunded or intubated patient — when clinical exam is unreliable, how do you make the diagnosis?
Key Classifications
Related Scenarios
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