The inferior extensor retinaculum of the foot (cruciate crural ligament, lower part of anterior annular ligament) is a Y-shaped band placed in front of the
ankle-joint, the stem of the Y being attached laterally to the upper surface of the
calcaneus
In humans and many other primates, the calcaneus (; from the Latin ''calcaneus'' or ''calcaneum'', meaning heel; : calcanei or calcanea) or heel bone is a bone of the Tarsus (skeleton), tarsus of the foot which constitutes the heel. In some other ...
, in front of the depression for the
interosseous talocalcaneal ligament
The interosseous talocalcaneal ligament forms the chief bond of union between the talus and calcaneus.
It is a portion of the united capsules of the talocalcaneonavicular and the talocalcaneal joints, and consists of two partially united layer ...
; it is directed medialward as a double layer, one lamina passing in front of, and the other behind, the tendons of the
peroneus tertius and
extensor digitorum longus.
At the medial border of the latter tendon, these two layers join, forming a compartment in which the tendons are enclosed.
From the medial extremity of this sheath, the two limbs of the Y diverge: one is directed upward and medialward, to be attached to the
tibial malleolus, passing over the
extensor hallucis longus and the vessels and nerves but enclosing the
tibialis anterior by a splitting of its fibers.
The other limb extends downward and medialward, to be attached to the border of the
plantar aponeurosis, and passes over the tendons of the extensor hallucis longus and tibialis anterior and also the vessels and nerves.
Additional images
File:Gray437.png, Muscles of the front of the leg.
File:Slide2ALE.JPG, Inferior extensor retinaculum of foot. Deep dissection.
See also
*
Cruciate ligament
References
{{Authority control
Lower limb anatomy