Wrist, Hand and Foot LO 6
6. Understand the organization of the fascia of the ankle and foot.
In the ankle region, the crural fascia thickens to form retinacula that hold tendons close to the bone, creating a sort of pulley system; so they do not pull away from the bone while muscles contract as tendons cross joints.
- superior extensor retinaculum: superior to the ankle, on the anterior aspect of the leg
- inferior extensor retinaculum: on the anterior aspect of the ankle. It is Y-shaped, extending onto the dorsum of the foot.
- flexor retinaculum: on the posteromedial aspect of the ankle
The deep fascia of the foot is continuous with the crural fascia of the leg. As in the leg, it divides the foot into muscular compartments, very similar to the muscular compartments of the hand. On the plantar surface, the central portion of the fascia is thick, dense connective tissue with longitudinally arranged fibers and forms the plantar aponeurosis (“plantar fascia”). The plantar fascia holds parts of the foot together and helps support the longitudinal arches of the foot. It arises posteriorly from the calcaneus, courses across the midfoot, and divides into five longitudinal bands distally that course into the digits.