Relationship of a low-lying muscle belly to tears of the peroneus brevis tendon.

A lack of information exists regarding predisposing factors to peroneus brevis tendon (PBT) tears. In 30 human cadaveric specimens, the location of the musculotendinous junction (MTJ) with respect to the fibula tip and peroneal tubercle was measured, as well as the tendon width. Degenerative longitudinal tears were found in 4 cases. The MTJ was significantly more distal and the tendon was thicker in torn versus untorn specimens (P < 0.05). The data suggest that longitudinal location of the peroneus brevis MTJ may have an influence on the development of degenerative tears. This feature might be an important clinical risk factor for the development of PBT tears and warrants further clinical investigation.