Intrinsic Muscles of the Hand Flashcards
Opponens pollicis insertion?
Lateral side of the 1st metacarpal
Opponens pollicis origin? (Thenar muscle)
Flexor retinaculum and tubercles of scaphoid and trapezium
Innervation of Opponens pollicis?
Recurrent branch of median nerve (C8, T1)
Actions of Opponens pollicis?
to oppose thumb; it draws 1st metacarpal medially to center of palm and rotates it medially.
Abductor pollicis brevis origin? (Thenar muscle)
Flexor retinaculum and tubercles of scaphoid and trapezium
Abductor pollicis brevis insertion?
Lateral side of base of proximal phalanx of thumb
Abductor pollicis longus innervation?
Recurrent branch of median nerve (C8, T1)
Abductor pollicis brevis action?
abducts thumb; helps oppose it
Flexor pollicis brevis (Superficial & Deep Head) (Thenar muscle) origin?
Flexor retinaculum and tubercles of scaphoid and trapezium
Flexor pollicis brevis (Superficial & Deep Head) insertion?
Lateral side of base of proximal phalanx of thumb
Flexor pollicis brevis (Superficial & Deep Head) innervation?
Superficial - Recurrent branch of median nerve (C8, T1)
Deep - deep branch of ulnar nerve c8, t1
Flexor pollicis brevis (Superficial & Deep Head)
flexes thumb
Adductor pollicis (Thenar muscle) origin?
Oblique head : bases of 2nd and 3rd metacarpals, capitate, adjacent carpals
Transverse head : Anterior surface of shaft of 3rd metacarpal
Adductor pollicis insertion?
Medial side of base of proximal phalanx of thumb
Adductor pollicis innervation?
Deep branch of ulnar nerve (C8, T1)
Adductor pollicis action?
adducts thumb toward lateral border of palm
Abductor digiti minimi (hypothenar muscle) origin?
Pisiform
Abductor digiti minimi insertion?
medial side of base of proximal phalanx of 5th finger
Abductor digiti minimi innervation?
Deep branch of ulnar nerve (C8, T1)
Abductor digiti minimi action?
abducts 5th finger, assits in flexion of its proximal phalanx
Flexor digiti minimi brevis (hypothenar muscle) origin?
Hook of hamate and flexor retinaculum
Flexor digiti minimi brevis insertion?
medial side of base of proximal phalanx of 5th finger
Flexor digiti minimi brevis innervation?
Deep branch of ulnar nerve (C8, T1)
Flexor digiti minimi brevis action?
flexes proximal phalanx of 5th finger
Opponens digiti minimi (hypothenar muscle) origin?
Hook of hamate and flexor retinaculum
Opponens digiti minimi insertion?
Medial border of 5th metacarpal
Opponens digiti minimi Innervation?
Deep branch of ulnar nerve (C8, T1)
Opponens digiti minimi action?
Draws 5th metacarpal anterior and rotates it, bringing 5th finger into opposition with thumb
Lumbricals (Short muscles) origin?
1 & 2: Lateral two tendons of flexor digitorum profundus (as unipennate muscles)
3 & 4: medial three tendons of flexor digitorum profundus ( as bipennate muscles)
Lumbricals insertion?
Lateral sides of extensor expansions of 2nd-5th fingers
Lumbricals innervation?
Median nerve (C8, T1)
Lumbricals action?
flex metacarpophalangeal joints; extend interphalangeal joints of 2nd-5th fingers
Dorsal interossei, 1-4 (Short muscle) origin?
Adjacent sides of two metacarpals (as bipennate muscles)
Dorsal interossei, 1-4 insertion?
Bases of proximal phalanges; extensor expansions of 2nd-4th fingers
Dorsal interossei, 1-4 innervation?
Deep branch of ulnar nerve (C8, T1)
Dorsal interossei, 1-4 actions?
Abduct 2nd-4th fingers from axial line; act with lumbricals in flexing metacarpophalangeal joints and extending interphalangeal joints
Palmar interossei, 1-3 (short muscle) origin?
Palmar surfaces of 2nd, 4th and 5th metacarpals (as unipennate muscles)
Palmar interossei, 1-3 insertion?
Bases of proximal phalanges; extensor expansions of 2nd, 4th, and 5th fingers
Palmar interossei, 1-3 innervation?
Deep branch of ulnar nerve (C8, T1)
Palmar interossei, 1-3 actions?
Adduct 2nd, 4th and 5th fingers toward axial line; assist lumbricals in flexing metacarpophalangeal joints and extending interphalangeal joints.
