Superior Fibular Retinaculum, Lateral View

Description

Along the lateral malleolus, the superior fibular retinaculum forms a thickened fascial band spanning from the posterolateral distal fibula toward the calcaneus, roofing the retrofibular groove. Deep to this sheath, the fibularis (peroneus) longus and fibularis brevis tendons course posterior to the fibula and then turn inferiorly toward the lateral aspect of the foot. The distal fibula lies superior and slightly anterior to the calcaneus, while the talus sits medial to the lateral malleolus within the ankle mortise, with the metatarsals and phalanges extending distally. Retinacular restraint at the lateral malleolus matters because it maintains the tendons in their correct line of pull during ankle dorsiflexion and eversion, when the fibular tendons are most likely to bowstring. Tear or laxity of the superior fibular retinaculum after an inversion injury can lead to recurrent fibular tendon subluxation or dislocation over the lateral malleolus, often accompanied by longitudinal split tears of fibularis brevis. This lateral exposure is also the key landmark for surgical repair techniques (retinacular imbrication, groove deepening) and for correlating MRI or ultrasound findings with the retromalleolar anatomy. A small structure. A common problem. Use this illustration to teach lateral ankle anatomy in gross anatomy, musculoskeletal ultrasound, and sports medicine modules, or to support operative atlases and journal figures discussing peroneal tendon instability and superior fibular retinaculum reconstruction. It also fits well in patient education materials explaining why posterolateral ankle pain can persist after a sprain despite normal radiographs. Anatomical accuracy verified by SciePro's Medical Advisory Board.