HAND & ARM Flashcards
(98 cards)
What are the 3 types of bones in the hands?
Carpal bones
Metacarpal bones
Phalanges
What are the carpal bones?
Scaphoid
Lunate
Triqetrum
Pisiform
Trapezium
Trapezoid
Capitate
Hamate
“Some Lovers Try Positions That They Can’t Handle”
Which of the carpal bones is a sesamoid bone?
The pisiform - it is formed within the tendon of the flexor carpi ulnaris
What are the metacarpal bones?
Metacarpal 1-5 for each finger
They articulate proximally with the carpals and distally with the proximal phalanges
What are the phalanges?
Bones of the fingers
Each digit has a proximal, middle and distal phalanx apart from the thumb which only has a proximal and distal phalanx.
What are the extrinsic and intrinsic muscles of the hand?
Extrinsic - located in anterior and posterior compartments of the forearm. Control crude movements and produce a forceful grip
Intrinsic - located within the hand itself. Responsible for the fine motor functions of the hand
What innervates the thenar muscles?
Median nerve
What are the thenar muscles?
Opponens pollicis
Abductor pollicis brevis
Flexor pollicis brevis
Function of opponens pollicis?
Opposes the thumb by medially rotating and flexing the metacarpal on the trapezium
Function of abductor pollicis brevis?
Abducts the thumb
Function of flexor pollicis brevis?
Flexes the MCP joint of the thumb
What innervates the hypothenar eminence?
Ulnar nerve
What are the hypothenar muscles?
Opponens digiti minimi
Abductor digiti minimi
Flexor digiti minimi brevis
Function of opponens digiti minimi?
Rotates the metacarpal of the little finger towards the palm, producing opposition
Function of abductor digiti minimi?
Abducts the little finger
Function of flexor digiti minimi brevis?
Flexes the MCP joint of the little finger
What innervates the lumbricals?
Lateral 2 - median nerve
Medial 2 - ulnar nerve
What hand muscles does the median nerve innervates?
LOAF
The lateral 2 lumbricals, opponens pollicis, abductor pollicis brevis and flexor pollicis brevis
All others are ulnar
Function of the lumbricals?
Flexion at MCPJ and extension at IPJs of each digit
Denervation of the lumbricals causes what…?
Ulnar claw
Hand of benediction
What is hand of benediction?
When there is a lesion of the median nerve so the middle and index fingers cannot flex at the MCP and IP joints
This is due to paralysis of the lateral 2 lkmbricals and the lateral half of flexor digitorum profundus
What is ulnar claw?
Lesion of an ulnar nerve which causes unopposed extension at the MCPjs and flexion at IPJs in the little and ring fingers
This is due to paralysis of the medial 2 lumbricals
What are the interossei muscles?
These are the muscles located between the metacarpal bones of the hand
They are divided into dorsal and planar
What innervates the interossei muscles?
Ulnar nerve