A 44 yo M presents to the ED w/ L foot and ankle pain. He was running and stepped into a hole, stating he heard a "crack". He has been unable to bear weight since the injury. On exam, he has swelling and marked bony tenderness of both the lateral and medial malleoli and heel. Xrays of the L foot were obtained. What's the diagnosis? (scroll down for answer)

 Answer: Comminuted fracture of calcaneus

• Etiology
• Most commonly due to high axial load injuries such as fall from height or MVC
• ** most common tarsal fracture
• Presentation
• Diffuse pain, swelling and ecchymosis after trauma
• Often unable to bear weight
• Deformity of heel or plantar arch on exam
• Mondor's sign- ecchymosis/hematoma that tracks along sole of foot (pathognomonic for calcaneal fracture)
• Diagnosis
• Plain radiographs of ankle/foot
• Harris view: calcaneus in axial view
• Non-contrast CT of the foot/ankle is the gold standard and assists with surgical planning
• Sander's Classification (based on CT)
• Type I: all intra-articular fractures that have < 2mm displacement, regardless of # of fracture lines/fragments
• Type II: two bony fragments involving posterior facet
• Type III: three bony fragments including depressed middle fragment
• Type IV: four comminuted bony fragments
• ED management
• assess NV status 
• analgesia, ice, elevation
• splinting, often with bulky Jones dressing
• ortho consult
• Most intra-articular fractures require surgical repair
• Most extra-articular fractures can be treated conservatively with 10-12 weeks of casting; pt discharged from ED non-weightbearing

 References:

Jiménez-Almonte JH, King JD, Luo TD, Aneja A, Moghadamian E. Classifications in Brief: Sanders Classification of Intraarticular Fractures of the Calcaneus. Clin. Orthop. Relat. Res. 2019 Feb;477(2):467-471