22. The Hand Flashcards
What type of joint are the interphalangeal joints?
Synovial hinge
What type of joint are the metacarpophalangeal joints?
Synovial condyloid
What type of joint are the carpometacarpal joints?
Thumb - synovial saddle
Digits - synovial plane
What type of joint are the intercarpal joints?
Synovial plane
What muscle tenses the palmar aponeurosis?
Palmaris longus
Origin of palmaris brevis?
Palmar aponeurosis
Flexor retinaculum
Insertion of palmaris brevis?
Dermis
Function of palmaris brevis?
Grip
Innervation of palmaris brevis?
Superficial ulnar nerve C8, T1
What are the muscles at the thenar eminance?
Abductor pollicis brevis
Flexor pollicis brevis
Opponens pollicis
Origin of abductor pollicis brevis?
Scaphoid
Trapezium
Insertion of abductor pollicis brevis?
Base of proximal phalanx of thumb
Function of abductor pollicis brevis?
CMC joint abduction
Innervation of abductor pollicis brevis?
Recurrent median nerve C8, T1
Origin of flexor pollicis brevis?
,Flexor retinaculum
Capitate
Trapzium
Insertion of flexor pollicis brevis?
Base of proximal phalanx of thumb
Function of flexor pollicis brevis?
CMC joint flexion
Innervation of flexor pollicis brevis?
Recurrent median nerve C8, T1
Origin of opponens pollicis?
Trapezium
Insertion of opponens pollicis?
First metacarpal
Function of opponens pollicis?
CMC joint opposition
Innervation of opponens pollicis?
Recurrent median nerve C8, T1
Origin of adductor pollicis?
Transverse head - 3rd metacarpal
Oblique head - capitate and 2nd/3rd metacarpals
Insertion of adductor pollicis?
Base of proximal phalanx of thumb
Function of adductor pollicis?
Adduction of CMC joint of thumb
Flexion of MCP joint of thumb
Innervation of adductor pollicis?
Deep ulnar nerve (C8, T1)
What muscles make up the hypothenar eminence?
Abductor digit minimi
Flexor digiti minimi
Opponens digiti minimi
Origin of abductor digiti minimi?
Pisiform
Insertion of abductor digiti minimi?
Base of 5th proximal phalanx
Dorsal digital expansion
Function of abductor digiti minimi?
Abduction and flexion MCP joint of little finger
Innervation of abductor digiti minimi?
Deep ulnar nerve C8, T1
Origin of flexor digiti minimi?
Hamate
Flexor retinaculum
Insertion of flexor digiti minimi?
Base of 5th proximal phalanx
Function of flexor digiti minimi?
Flex MCP joint of little finger
Innervation of flexor digiti minimi?
Deep ulnar neve (C8, T1)
Origin of opponens minimi?
Hamate
Flexor retinaculum
Insertion of opponens minimi?
5th metacarpal
Function of opponens minimi?
Weak opposition of little finger
Innervation of opponens minimi?
Deep ulnar nerve C8, T1
How many lumbricals are there?
4
Which of the lumbricals are unipennate and which are bipennate?
1+2 = uni
3+4= bi
From which structure do the lumbricals arise?
Tendons of flexor digitorum profundus
Insertion of lumbricals?
Dorsal digital expansion
Function of lumbricals?
MCP joint FLEXION
IP joint EXTENSION
(because they run anterior and posterior)
For digits 2 - 5
Innervation of lumbricals?
1+2 = digital branch of median nerve C8, T1 3+4 = deep ulnar nerve C8, T1
Between which bones are the palmar interossei found?
Metacarpals
How many palmar interossei are there?
3
Origin of palmar interossei?
1st - 2nd MCP
2nd - 4th MCP
3rd - 5th MCP
Insertion of palmar interossei?
All to dorsal expansion PLUS:
1st - 2nd proximal phalanx
2nd - 4th proximal phalanx
3rd - 5th proximal phalanx
Function of palmar interossei?
Adduction towards middle finger (PAD)
Innervation of palmar interossei?
Deep ulnar nerve C8, T1
Origin of dorsal interossei?
From sides of 2 adjacent metacarpals
Insertion of dorsal interossei?
To dorsal digital expansion PLUS
1st - 2nd proximal phalanx
2nd and 3rd - 3rd proximal phalanx
4th - 4th proximal phalanx
How many dorsal interossi are there?
4
Function of dorsal interossei?
Abduction (DAB)
Innervation of dorsal interossei?
Deep ulnar nerve C8, T1
Is there superficial palmar arch mostly from the radial or ulnar artery?
Ulnar
Is the deep palmar arch mostly from the radial or ulnar artery?
Radial
Which artery runs through the anatomical snuffbox?
Radial
Name the 2 spaces and 1 tunnel within the hand
Palmar space
Thenar space
Lumbrical tunnel
What dermatome is at the tip of the middle finger?
C7 (can work out rest using this)
What is the general rule for innervation of the hand?
ALL ULNAR EXCEPT ‘LOAF’
Lumbricals (first two)
Opponens pollicis
Abductor pollicis brevis
Flexor pollicus brevis
Is the radial nerve motor or sensory within the hand?
Sensory in hand (motor in posterior forearm)