Structure
The inferior fibular retinaculum is a fibrous band of deep fascia and is regarded as a continuation of the inferior extensor retinaculum and extends posteriorly to the lateral aspect of the calcaneus. Some fibers attach to the fibular trochlea of the calcaneus.
Anatomical Relations
The tendons of the fibularis longus and brevis muscles share a common tendinous sheath proximal to the inferior fibular retinaculum. Some fibers from the inferior fibular retinaculum attach to the fibular trochlea of the calcaneus, thus separating the common tendinous sheath. The fibularis longus tendon passes inferior to the fibular trochlea, while the fibularis brevis passes superior.
Function
The inferior fibular retinaculum holds the tendons of the fibularis longus and brevis in place and prevents subluxation of the tendons.
