Flexor Retinaculum of Foot

The laciniate ligament (internal annular ligament, flexor retinaculum of foot) is a strong fibrous band, extending from the tibial malleolus above to the margin of the calcaneus below, converting a series of bony grooves in this situation into canals for the passage of the tendons of the Flexor muscles and the posterior tibial vessels and tibial nerve into the sole of the foot.

It is continuous by its upper border with the deep fascia of the leg, and by its lower border with the plantar aponeurosis and the fibers of origin of the Abductor hallucis muscle.

Enumerated from the medial side, the four canals which it forms transmit the tendon of the Tibialis posterior; the tendon of the Flexor digitorum longus; the posterior tibial vessels and tibial nerve, which run through a broad space beneath the ligament; and lastly, in a canal formed partly by the talus, the tendon of the Flexor hallucis longus.

The entrapment of the tibial nerve beneath the flexor retinaculum causes the tarsal tunnel syndrome, characterized by pain, numbness and tingling of the medial plantar surface of the foot. The situation is aggravated by standing and walking, and often worse at night.

Famous quotes containing the word foot:

    The foot of the heavenly ladder, which we have got to mount in order to reach the higher regions, has to be fixed firmly in every-day life, so that everybody may be able to climb up it along with us. When people then find that they have got climbed up higher and higher into a marvelous, magical world, they will feel that that realm, too, belongs to their ordinary, every-day life, and is, merely, the wonderful and most glorious part thereof.
    —E.T.A.W. (Ernst Theodor Amadeus Wilhelm)