Which muscle does not take pa in dorsal digital expansion
DORSAL DIGITAL EXPANSION: The dorsal digital expansion {extensor expansion} is a small triangular aponeurosis covering the dorsum of the proximal phalanx. Its base, which is proximal, covers the metacarpophalangeal joint. The main tendon of the extensor digitorium occupies the central pa of the extension and is separated from the MP joint by a bursa. The posterior corners of the extensor expansion are joined by tendons of the interossei {proximal} and {distal} are often called' wing tendons' Near the proximal interphalangeal joint, the extensor tendon divides into a central slip and two collateral slips. The central slip is joined by some fibres from the margins of the expansion, crosses the proximal interphalangeal joint, and is inseed on the dorsum of the base of the middle phalanx. The two collateral slips are joined by the remaining thick margin of the extensor expansion. They then join each other and are inseed on the dorsum of the base of the distal phalanx. As the metacarpophalangeal and interphalangeal joints, the extensor expansion forms the dorsal pa of the fibrous capscule of the joints. The retinacular ligaments {limk ligaments} extend from the side of the proximal phalanx, and form its fibrous flexor sheath, to the margins of the extensor expansion to reach the base of the distal phalanx. THE MUSCLES INSEED INTO THE DORSAL DIGITAL EXPANSION OF: INDEX FINGER: First dorsal interosseous, second palmar interosseous, first lumbrical, extensor digitorum slip, and extensor indicis. MIDDLE FINGER: Second and third dorsal interossei, second lumbrical, extensor digitorum slip. RING FINGER: Fouh dorsal interosseous, third palmar interosseous, third lumbrical and extensor digitorum slip. LITTLE FINGER: Fouh palmar interosseous, fouh lumbrical, extensor digitorum slip and extensor digiti minimi.
Interossei
Lumbricals
Extensor digitorum
Adductor pollicis
Upper limb