Muscles of the Forearm Flashcards
Movements of the hand at the wrist joint
Extension
Flexion
Abduction (lateral/radial deviation)
Adduction (medial/ulnar deviation)
Movements of the thumb
It is rotated 90 deg with respect to digits
So spreading all digits out, that is extension of the thumb
Sticking thumb straight up is abduction
4 carpals in proximal row
Scaphoid
Lunate
Triquetrum
Pisiform
4 carpals in distal row
Trapezium
Trapezoid
Capitate
Hamate
Radiocarpal/wrist joint is between which bones?
Radius, scaphoid and lunate
How many phalanges does the thumb have?
2
Power grip
Muscles of the forearm that insert into the hand and allow for forceful gripping with the hand
Extrinsic muscles of the hand
Almost all of the muscles in the anterior forearm are innervated by which nerve?
Median nerve
Which muscles in the anterior compartment of the forearm are innervated by the ulnar nerve?
Flexor carpi ulnaris
Medial half of the flexor digitorum profundus
4 muscles in the superficial layer of the anterior compartment of the forearm
Pronator teres
Flexor carpi radialis
Palmaris longus
Flexor carpi ulnaris
Flexor retinaculum
Thick band of membranous connective tissue that holds the tendons in place
Muscle in the middle layer of the anterior compartment and its functions
Flexor digitorum superficialis
Attaches to the middle phalanges of the 4 fingers
Has 4 tendons
Flexes fingers at the PIP joints
PIP joints
Proximal interphalangeal joint
3 muscles in the deep layer of the anterior compartment
Flexor digitorum profundus
Flexor pollicus longus
Pronator quadratus
Function of the Flexor digitorum profundus
Attaches to the distal phalanges of the 4 fingers
Has 4 tendons
Flexes fingers at the DIP joints
Carpal tunnel
Floor is the carpal bones
Roof is the flexor retinaculum
9 tendons and 1 nerve pass through (4 tendons from superficials, 4 from profundus, 1 from pollicus longus, and median nerve)
The posterior compartment of the forearm is innervated by which nerve?
Radial nerve
Which muscle extends the fingers?
Extensor digitorum (with 4 tendons)
5 muscles in the superficial layer of the posterior compartment of the forearm
Brachioradialis Extensor carpi radialis (longus and brevis) Extensor digitorum Extensor digit minimi Extensor carpi ulnaris
Brachioradialis
Attaches anteriorly to distal radius
Flexor of elbow/forearm
Considered to be in the posterior compartment because its innervated by the radial nerve
3 muscles in the deep layer of the posterior compartment
Extensory pollicis brevis
Extensor pollicis longus
Extensor indicis
2 extensors of the thumb
Extensor pollicis (longus and brevis)
Extensor of
- Index finger
- Pinky finger
- Extensor indicis
2. Extensor digit minimi
The tendons of which muscle splits to allow distal attachment on the phalanges?
Tendons of the flexor digitorum superficialis split and attach to the middle phalanges
Tendons of the digitorum profundus move through the split and attach to the distal phalanges
What muscle(s)
- Pronates the forearm
- Supinates the forearm
- Pronator teres, pronator quadratus
2. Biceps brachii