Hand Flashcards
Peripheral nerve innervation of hand
Ulnar n.
- dorsal cutaneous branch of ulnar n.
Median n.
Radial n.
-radial n. superficial branch
Dermatomes of the hand
C6
C7
C8
Carpal tunnel framework
formed by the arching alignment of the carpal bones and the thick flexor retinaculum (transverse carpal ligament)
Carpal tunnel contents
Median n.
1 Flexor pollicis longus tendon
4 flexor digitorum profundus tendons
4 flexor digitorum superficialis tendons
Fascia of the hand
Palmar fascia is thin over thenar and hypothenar eminences (thenar fascia, hypothenar fascia)
Thick centrally forming the palmar aponeurosis and in the fingers forming the digital sheaths
Dupuytren’s contracture/disease
Palmar node, usually 4th or second digit at the MCP joint then the prox IP joint
nodules in fascia = loss of ROM and some pain
30% sporadic
1-2% of population - more in men
Dupuytren’s diathesis - more aggressive form
Trauma and occupational
Intrinsic muscle of the hand
Palmar brevis m.
Thenar eminence mm.
Adductor pollicis m.
Hypothenar eminence mm.
Interossei mm.
Lumbrical mm.
Movements of the thumb
extension
flexion
abduction
adduction
opposition
Palmar brevis muscle
O: palmar aponeurosis and flexor retinaculum
I: Dermis of skin
Inn: Superficial branch of ulnar n.
Actions: improves grib
ABductor pollicis brevis muscle
Inn: reccurent branch of median n.
Actions: ABducts pollex - helps with opposition
Flexor pollicis brevis muscle
Inn: recurrent branch of median n.
Actions: flexes pollex
Has two heads
Opponens pollicis muscle
Inn: recurrent branch of median n.
Actions: opposes pollex toward center of palm and rotates it medially
Abductor digiti minimi muscle
O: pisiform
I: medial side of base of prox. phalanx of digit 5
Inn: deep branch of ulnar n.
Actions: ABducts digit 5 (assists in flexion of proximal phalanx)
Flexor digiti minimi brevis muscle
Inn: deep branch of ulnar n.
Actions: flexes digit 5
Opponens digiti minimi muscle
Inn: deep branch of ulnar n.
Actions: draws 5th metacarpal anteriorly and rotates it (brings digit 5 into opposition with pollex)
Adductor pollicis muscle
O: had two heads that origin from the base of metacarpals
I: medial side of base of proximal phalanx or pollex
Inn: deep branch of ulnar n.
Actions: adducts pollex
Lumbrical muscles
O: tendons of flexor digitorum profundus m.
I: 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 joint and extends IP joints (digits 2-5)
Dorsal interossei muscles
O: Adjacent sides of metacarpals
I: extensor hood and base of prox. phalanges of digits 2-4
Inn: deep branch of ulnar n.
Actions: ABducts digits 2-4
assists lumbrcials in flex MCP and extend IP joints
DAB
Palmar interossei muscles
O: sides of metacarpals (digits 2,4,5)
I: 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 the hand
Deep palmar artery
Superficial palmar arch
- Common palmar digital aa.
- Proper palmar digital aa.
Anatomical snuff box
Lateral: ABductor pollicis longus tendon and extensor pollicis brevis tendon
Medial: extensor pollicis longus tendon
Floor: scaphoid trapezium
Contents: radial artery
Median nerve branches in hand
Palmar branch
Recurrent branch
Common palmar digital nn.
- proper palmar digital nn.
Ulnar nerve branches in hand
Palmar branch
Deep branch
Superficial branch
common palmar digital n.
proper palmar digital nn.
Radial nerve branches in hand
Superficial branch - all sensory in the hand
Dorsal digital n.
terminal branch of dorsal digital branches
