An avulsion fracture of the anterior process of the calcaneus results from pull of which ligament?

• A. Bifurcate ligament
• B. Kagers' fat pad
• C. Deltoid ligament
• D. Posterior talofibular ligament

Answer: (A)

An avulsion fracture of the anterior process of the calcaneus happens when a ligament anchoring near that front part of the heel pulls on the bone with enough force to detach a fragment. The bifurcate ligament, which splits into two bands to attach to the navicular and the cuboid, has its calcaneal attachment at the anterior aspect of the calcaneus. In forceful foot movements, especially inversion injuries, that traction pulls on the calcaneal insertion and can avulse the anterior process. The other structures listed don’t originate from or exert traction at that anterior calcaneal region: the deltoid ligament is medial, the posterior talofibular ligament is posterior-lateral, and Kager’s fat pad is just a fat pad, not a ligament capable of causing this avulsion.