Low lying peroneus brevis muscle belly

Low lying peroneus brevis muscle belly (LLPB) is a rare congenital anomaly that makes the tendon more prone to tendon tear and subluxation . This condition is defined by the extension of the muscle belly to the level of the fibular groove.

Differential diagnosis

Peroneus quartus muscle - as an accessory peroneal muscle - should be distinguished from LLPB. Peroneus quartus forms a distinct myotendinous structure in the peroneal compartment with variable lateral insertion.