The extensor retinaculum is a strong, fibrous band, extending obliquely downward and medialward across the back of the wrist.

[3][clarification needed] On the dorsal side of the hand, the palmar carpal ligament corresponds in location and structure to the extensor retinaculum, both being formations of the antebrachial fascia and therefore continuous.

Combined these three layers create a smooth gliding surface as well as mechanically strong tissue which prevents tendon bowstringing.

A graft of the extensor retinaculum was shown to be useful in treating boxer's knuckle when direct repair of the damaged capsule is not possible.

[6] Because of their similarities in histological structure, studies also show the extensor retinaculum to be a reasonable biological replacement for reconstruction of a deficient annular pulley.