"origin: palmar surface of 2nd, 4th and 5th metacarpal bones"
"insertion: extensor hood and the base of the proximal phalanges of their related digits"
"innervation: deep branch of the ulnar nerve (C8, T1)"
"action"
"Palmar = ADduction"
"Palmar = ADduction"
"Dorsal = ABduction"
"Dorsal = ABduction"
"The mnemonic “PAD” and “DAB” can be used to help remember the different functions of the two muscle groups."
"Palmar = ADduction"
"Dorsal = ABduction"
"Palmar = ADduction"
"Dorsal = ABduction"
Expected headings
"Blood supply"
"Clinical pearls"
"Clinical testing"
"The interossei muscles, form part of the intrinsic muscles of the hand, and as a group consisting of four palmar (1st is often rudimentary) and four dorsal muscles. Collectively the interossei contribute to abduction and adduction of the fingers and also contribute to flexion of the metacarpophalangeal joints (MCPJ) and extension of the interphalangeal joints (IPJ) through their insertion onto the extensor hood. The reference axis through which abduction and adduction occur is the long axis of the 3rd phalanx (middle finger)."
"primary: adduction of thumb, Index, ring and little fingers at the MCPJ joints; NB: the middle finger cannot adduct"
"The palmar interossei muscles of the hand are unipennate and more volar in relation to the dorsal interossei. There are four muscles in this group, however, the 1st is rudimentary and often considered part of either the adductor pollicis or the flexor pollicis brevis 1,3. They adduct the thumb, index, ring and little fingers along the long axis of the middle finger. Just like the dorsal interossei, the tendons pass deep to the transverse metacarpal ligament."
"primary: adduction of thumb, Index, ring and little fingers at the MCPJ joints; NB: the middle finger cannot adduct"
"The palmar interossei muscles of the hand are unipennate and more volar in relation to the dorsal interossei. There are four muscles in this group, however, the 1st is rudimentary and often considered part of either the adductor pollicis or the flexor pollicis brevis 1,3. They adduct the thumb, index, ring and little fingers along the long axis of the middle finger. Just like the dorsal interossei, the tendons pass deep to the transverse metacarpal ligament."
"There is no palmar interosseous muscle for the third digit as it cannot be adducted towards itself."