Description of the episeptal and interlaminar fascial tunnels for the superficial fibular nerve and its terminal branches.

PURPOSE: This study aimed to reveal the course of the superficial fibular nerve and its branches, whose entrapment may be responsible for anterior leg pain and is at risk in fasciotomies, according to the crural fascia laminae and the anterior intermuscular septum. METHODS: On the twenty cadaver legs, the location of the superficial fibular nerve and its branches, according to the crural fascia layers and anterior intermuscular septum, the course type in the tunnel, if any, and the superficialization pattern were defined. RESULTS: The number of cases in which the superficial fibular nerve and its branches traveled within a tunnel was found to be 15/20 (75%). The superficial fibular tunnel was defined as an “episeptal” and “interlaminar fascial” tunnel based on the nerve’s relationship with the fascia layers and anterior intermuscular septum. In 45% of the cases, the distance the nerve traveled within the tunnel exceeded 3 cm. The finding that the superficial fibular tunnel exceeds 3 cm in 45% of cases suggests that, contrary to what is attributed in the literature, pain due to nerve compression cannot be explained solely by the presence and length of the tunnel. Other possible structural factors were whether the tunnel was episeptal or interlaminar fascial, whether the superficial exit level of the nerve was in which quadrant (thinner/thicker, stiffer/elastic) of the crural fascia. CONCLUSION: The data provided on these factors were evaluated based on the compression and traction effects that may be reflected on the superficial and deep layers at the entry and exit points of the tunnel.