Anatomical basis for pressure on the common peroneal nerve.

An attempt was made to explain the anatomical basis for the pressure on the common peroneal nerve which may lead to loss of sensation and "foot drop". By using available cadavers during routine dissections, it was observed that the attachments of the peroneus longus muscle on the head of the fibula are, in most cases, tendinous, and blended with the crural fascia and lateral (fibular) ligament, thereby, forming an inelastic band arching over the common peroneal nerve. In some other cases, the reflected fibres of the biceps femoris tendon, anterior tibiofibular ligament and iliotibial tract constituted a fibrous bridge over the nerve. The least occurrence was that of the nerve piercing the thick and inelastic anterior crural septum.