tendinous sheath of extensor carpi radialis muscles

tendinous sheath of ex·ten·sor car·pi ra·di·a·lis mus·cles

[TA] the dorsal carpal synovial tendon sheath lining the compartment of the extensor retinaculum containing the tendons of the extensor carpi radialis longus and brevis muscles. Synonym(s): vagina tendinum musculorum extensorum carpi radialium [TA]