Muscles of the hand Flashcards
What are the thenar muscles?
What innervates them?
Three short muscles located at the base of the thumb. The muscle bellies produce a bulge known as the thenar eminence.They produce fine movements of the thumb
Median nerve
What is opponens pollicis
What innervates it
Largest of the thenar muscles, sits deep to the others.
Median nerve
What are the attachments of opponens pollicis
What are its functions?
Originates from the tubercles in the trapezium and the associated flexor retinaculum. It inserts into the lateral margin of the metacarpal of the thumb.
Opposes thumb, medially rotates and flexes metacrpal on the trapezium
What is the abductor pollicis brevis?
What innervates it
Thenar muscle
Median nerve
What are the attachments of the abductor pollicis brevis
What is its function?
Originates from the tubercles of the scaphoid and trapezium and from the associated flexor retinaculum. Attaches to the proximal phalanx of the thumb
Abducts the thumb
What is flexor pollicis brevis?
what innervates it?
Most distal of the thenar muscles
Median nerve
What are the attachments of Flexor pollicis brevis?
What is its function?
Originates form the tubercle of the trapezium and from the associated flexor retinaculum. Attaches to the base of the proximal phalanx of the thumb
Flexes the metacarpophalangeal (MCP) joint of the thumb.
What are the hypothenar muscles?
What innervates them?
Muscles of the pinky finger. They form a hypothenar eminence on the ulnar aspect of the hand
Ulnar nerve
What is the opponens digit minimi?
What innervates it?
Deepest hypothenar muscle
Ulnar nerve
What are the attachments of the opponens digiti minimi
What is its function
Originates from the hook of hamate and associated flexor retinaculum, inserts into the medial margin of metacarpal 5
Rotates the metacarpal of the little finger towards the palm
What is the abductor digiti minimi?
What innnervates it?
Most superficial hypothenar muscel
Ulnar nerve
What are the attachments of the abductor digit minimi
What is its function?
Originates from the psifirom and the tendon of the flexor carpi ulnaris.It attches to the base of the proximal phalanx of the little finger.
It abducts the thumb
What is flexor digiti minimi brevis?
What innervates it?
Hypothenar muscle
Ulnar nerve
What is the attachments of flexor digiti minimi brevis?
What is its function?
Originates from the hook of hamate and adjacent flexor retinaculum, inserts into the base of the proximal phalanx of the little finger.
Flexes the MCP joint of the little finger
What are the lumbricals?
What innervates them?
Four in each hand, very crucial to finegr movement they link extensor tendons and flexor tendons
Index and middle fingers- Median nerve
Little and ring fingers- Ulnar nerve
What are the actions of the lumbricals
What are there functions?
Each originate from a tendon of the flexor digitorum profudus. They pass dorsally and laterally around each finger and insert into the extensor hood
Flex the MCP joint, extend at the ICP joints of each finger
What are the interossei?
What innervates them?
Muscles located between metacarpals. They can be divided into two groups: dorsal and palmar. They act to assist in adduction and abduction of the fingers as well as flexion and extension at the MCP joints
Dorsal-abduct
palmar-adduct
Ulnar nerve
What is palmaris brevis?
What innervates it?
Small muscel of the hand found in the hypothenar eminence
Ulnar nerve
What are the attachements of palmaris brevis?
What are its actions?
Originates from the palmar aponeurosis and felxor retinaculum, attaches to the dermis of the skin on the medial margin of the hand
Improving grip- wrinkles the skin of the hypothenar eminence and deepens the curvature of the hand improving grip
What is abductor pollicis?]
What innervates it?
A large triangluar msucel with two heads. The radial artery passes anteriorly through the space between the two heads forming the deep palmar arch.
Ulnar nerve
What are the attachments of adductor pollicis?
What are its actions
One head originates from metacarpal III. The other head originates from the capitate and the adjacent areas of metacarpals II and III. Both attach into the base of the proximal phalanx of the thumb
Adductor of the thumb
