Hand Flashcards
Cutaneous innervation in hand
ulnar, median, radial nn
dermatomes of hand
Anterior: C6, C7, C8
Posterior: C7, C8
Carpal Tunnel Framework
formed by the arching alignment of the carpal bones and the thick flexor retinaculum (transverse carpal ligament)
fascia of hand
palmar fascia is thin over thenar and hypothenar eminences
thick centrally forming palmar aponeurosis and in the fingers forming the digital sheaths
Dupuytren’s Contracture/Disease
Palmar node, usually 4th or 2nd digit at MCP joint then the proximal IP joint
Dupuytren’s Diathesis is more aggressive form
trauma and occupationally acquired: repeated blows to palm and occupational stress
hands get stuck in contracture and lose range of motion
Palmaris Brevis
Origin: palmar aponeurosis and flexor retinaculum
Insertion: dermis of skin
Inn: superficial branch of ulnar n
Action: improves grip
Abductor Pollicis Brevis
Inn: Recurrent branch of median n
Action: abducts pollex, helps with opposition
Flexor Pollicis Brevis
Inn: recurrent branch of median n
Action: flexes pollex
Opponens Pollicis
Inn: recurrent branch of median n
Action: opposes pollex toward center of palm and rotates it medially
thumbs to fingers
Abductor Digiti Minimi
Origin: pisiform
Insertion: digit 5
Inn: deep branch of ulnar n
Action: abducts digit 5, assists in flexion of proximal phalanx
Flexor Digiti Minimi Brevis
Origin: hook of hamate, flexor retinaculum
Insertion: digit 5
Inn: deep branch of ulnar n
Action: flexes digit 5
Opponens Digiti Minimi
Origin: hook of hamate, flexor retinaculum
Insertion: palmar surface of 5th metacarpal
Inn: deep branch of ulnar n
Action: draws 5th metacarpal anteriorly and rotates it, brings digit 5 into opposition with pollex
Adductor Pollicis
Origin: oblique head: bases of 2nd and 3rd metacarpals
transverse head: ant. surface of body of 3rd metacarpal
Insertion: Base of prox. phalanx of pollex
Innervation: deep branch of ulnar n
Actions: adducts pollex
Lumbrical Muscles
Origin: tendons of flexor digitorum profundus m
Insertion: Lateral sides of extensor expansion (digits 2-5)
Inn: median n (lumbricals 1-2)
Deep branch of ulnar n (lumbricals 3-4)
Actions: flexes digits at MCP joings and extend IP joints (digits 2-5)
Dorsal Interossei Muscles
Origin: adjacent sides of metacarpals
Insertion: extensor hood and base of prox. phalanges of digits 2-4
Inn: deep branch of ulnar n
Actions: abducts digits 2-4, assists lumbricals in flex MCP and extend IP joints (DAB)
Palmar Interossei Muscles
Origin: sides of metacarpals (digits 2,4,5)
Insertion: extensor expansion of digits 2, 4, 5 and base of prox. phalanx
Inn: deep branch of ulnar n
Actions: adducts digits 2, 4, 5; assists lumbricals in flex MCP and extend IP joints (PAD)
Arteries of Hand
one branch: deep palmar
swings laterally across palm to form superficial palmar arch; gives rise to common palmar digital aa and proper palmar digital aa
deep palmar arch branches
palmar metacarpal aa
perforating branches
Anatomical Snuff Box
Borders:
Lateral: abductor pollicis longus tendon and extensor pollicis brevis tendon
Medial: extensor pollicis longus tendon
Floor: Scaphoid and trapezium
what does the anatomical snuff box contain
radial artery
veins of hand
deep- accompany aa of the same name
superficial- dorsal venous network, cephalic, basilic
median nerve branches in hand
palmar, recurrent, common palmar digital nn, proper palmar digital nn
ulnar nerve branches in hand
palmar branch- branches at anterior forearm
deep branch
superficial branch- common palmar digital n and proper palmar digital nn
radial nerve branches in hand
superficial branch
all sensory in hand
what action does myotome C8 test
ulnar deviation
thumb extension
what action does myotome T1 test
finger abduction
