Muscles Of The Hand Flashcards
Name the thenar muscles
Opponens pollicis
Abductor pollicis brevis
Flexor pollicis brevis
What are the thenar muscles mostly responsible for?
Opposition of the thumb
Which nerves innervate the thenar muscles?
Median
What does the flexor pollicis brevis do? (Of the thenar muscles)
Flexes MCP joint of the thumb
What does the abductor pollicis brevis do? (Of the thenar muscles)
Abducts the thumb
Action of the opponens pollicis? (Thenar muscle)
Opposes the thumb
Name the hypothenar muscles
Opponens digiti minimi
Abductor digiti minimi
Flexor digiti minimi brevis
What are the hypothenar muscles innervated by?
The ulnar nerve
Action of the opponens digiti minimi? (Hypothenar muscle)
Opposes the little finger
Action of the abductor digiti minimi?
Abducts the little finger
Action of the flexor digiti minimi brevis? (Hypothenar)
Flexes the MCP joint of little finger
Where is the palmaris brevis?
Subcutaneous tissue of the hypothenar eminence.
What is the palmaris brevis innervated by?
The ulnar nerve
Action of the palmaris brevis?
Wrinkles skin of hypothenar eninenence
Deepens hollow of the palm - aiding palmar grip
Action of the lumbricals?
Flex the fingers at the metacarpophalangeal joints and extend the interphalangeal joints
Innervation of the lumbricals?
1st and 2nd - median nerve
3rd and 4th - ulnar nerve
Action of the dorsal interossei?
Abduct 2nd - 4th digits (DAB)
With the lumbricals, flex metacarpophalangeal joints and extend interphalangeal joints
Action of the palmar interossei?
Adduct 2nd, 4th and 5th digits (PAD)
Assist lumbricals in flexing metacarpophalangeal joints and extending interphalangeal joints.
Innervation of the interossei?
Ulnar
Innervation of the adductor pollicis?
Ulnar nerve
Action of the adductor pollicis?
Adducts the thumb
What passes between the two heads of the adductor pollicis?
The radial nerve. Forms the deep palmar arch
What is the hand of Benediction a result of?
Damage to the median nerve.
Which muscle are paralysed in the hand of benediction?
All the flexors in the anterior compartment of the forearm except for the medial half of the flexor digitorum profundus and the flexor carpi ulnaris
Lateral two lumbricals of the middle and index fingers
What happens in a hand of benediction?
The patient tries to make a fist. Can only flex medial two fingers.
Which muscles are paralysed in the ulnar claw?
Medial two lumbricals
Interossei
Hypothenar muscles
Adductor pollicis
Medial half of flexor digitorum profundus
Flexor carpi ulnaris
What is seen in ulnar claw?
MCP joints of little and ring finger are hyperextended by unopposed extension of extensor digitorum
IP joints of little and ring finger are flexed by unopposed flexion from flexor digitorum profundus
