Muscles of the forearm Flashcards
What are the muscles in the superficial layer of the anterior compartment of the forearm?
(distal-medial)
Pronator teres
Flexor carpi radialis
Palmaris longus
Flexor carpi ulnaris
Where is the common flexor origin (CFO)?
Anterior aspect of medial epicondyle
What is the function of the pronator teres?
Pronation of the forearm
What is the function of the flexor carpi radialis?
Flexes the wrist
Abducts the wrist
Stabilises wrist in powerful finger movements
What is the function of the palmaris longus?
Flexes the wrist
Tenses palmar fascia
What is the function of the flexor carpi ulnaris?
Adducts and flexes the wrist
Which nerve supplies the pronator teres?
Median
Which nerve supplies the flexor carpi radialis?
Median
Which nerve supplies the palmaris longus?
Median
Which nerve supplies the flexor carpi ulnaris?
Ulnar
Where is the origin of the pronator teres?
CFO
Distal part of supracondylar ridge of humerus
Medial aspect of coronoid process
Where is the origin of the flexor carpi radialis?
CFO
Where is the origin of the palmaris longus?
CFO
Where is the origin of the flexor carpi ulnaris
CFO
medial margin of olecranon process of ulna
Where is the insertion of the pronator teres?
Maximum convexity of the radius at the midpoint of the lateral aspect of the bone
Where is the insertion of the flexor carpi radialis?
Bases of second and third metacarpals
Where is the insertion of the palmaris longus?
Palmar aponeurosis with a superficial tendon adherent to the flexor retinaculum
Where is the insertion of the flexor carpi ulnaris?
Pisiform, hook of hamate and base of 5th metacarpal
What is the muscle in the intermediate layer of the anterior compartment of the forearm?
Flexor digitorum superficialis
Where is the origin of the flexor digitorum superficialis?
Humero-ulanr head:
CFO
Coronoid process
ulnar collateral ligament of elbow joint
Extended origin from radius
Where is the insertion of the flexor digitorum superficialis?
Radial and ulnar aspects of the base of the middle phalanx
What is the function of the flexor digitorum superficialis?
Flexor of wrist and fingers (excluding distal interphalangeal joints)
Weak flexor of the elbow
Which nerve supplies the flexor digitorum superficialis?
Median
What are the 3 muscles in the deep layer of the anterior compartment of the forearm?
Flexor digitorum profundus
Flexor pollicus
Pronator quadratus
Where is the origin of the flexor digitorum profundus?
Ulna and adjacent interosseous membrane
Where is the insertion of the flexor digitorum profundus?
Base of terminal phalanges
What is the function of the flexor digitorum profundus?
Flexion of interphalangeal joints, metacarpalphalangeal joints and the wrist
Which nerve supplies the flexor digitorum profundus?
Median nerve (radial 2 fingers)
Ulnar nerve (ulnar 2 fingers)
Where is the origin of the flexor pollicis longus?
Anterior surface of distal radius
Where is the insertion of the flexor pollicis longus?
Base of distal phalanx of thumb
What is the function of the flexor pollicis longus?
Flexor of thumb
Which nerve supplies the flexor pollicis longus?
Anterior branch of median nerve
Where is the origin of the pronator quadratus?
Anterior surfaces of distal radius and ulna
What is the function of the pronator quadratus?
Pronation of forearm
Which nerve supplies the pronator quadratus?
Anterior interosseous branch of median nerve
What are the 7 muscles in the superficial layer of the posterior compartment of the forearm?
Anconeus Brachioradialis Extensor carpi radialis longus Extensor carpi radialis brevis Extensor digitorum communis Extensor digiti minimi Flexor carpi ulnaris
Where is the origin of the anconeous?
CEO
Where is the CEO (common extensor origin)
Posterior aspect of lateral epicondyle
Where is the insertion of the anconeous?
Lateral aspect of proximal ulna
What is the function of the anconeous?
Pronation
Extends elbow
Which nerve supplies the anconeous?
Radial
Where is the origin of the brachioradialis?
Upper 2/3 of the lateral supracondylar ridge of the humerus
Where is the insertion of the brachioradialis?
Radial styloid process
What is the function of the brachioradialis?
Flexes elbow in position midway between pronation and supination (drinking muscle)
Which nerve supplies the brachioradialis?
Radial
Where is the origin of the extensor carpi radialis longus?
Distal 1/3 of lateral supracondylar ridge of humerus
Where is origin of the extensor carpi radialis brevis?
CEO
Where is the insertion of the extensor carpi radialis longus?
Base of second and third metacarpals
Where is the insertion of the extensor carpi radialis brevis?
Base of second and third metacarpals
Which nerve supplies the extensor carpi radialis brevis?
posterior interosseous branch of the radial nerve
Which nerve supplies the extensor carpi radialis longus?
Radial
What is the position of the wrist when the ECRL and ECRB act with the extensor carpi ulnaris?
Neutrally extended
What happens to the wrist when the ECRL and ECRB act with the flexor carpi radialis?
Pulled into radial deviation
Where is the origin of the extensor digitorum communis?
CEO
Where is the insertion of the extensor digitorum communis?
4 tendons: 1 in each phalange
What is the function of the extensor digitorum communis?
Main extensor of fingers
Which nerve supplies the extensor digitorum communis?
Posterior interosseous
Where is the origin of the digiti minimi?
CEO
Where is the insertion of the digiti minimi?
Medial aspect of dorsal expansion of little finger
What is the function of the digiti minimi?
Extension of little finger
Which nerve supplies the digiti minimi?
Posterior interosseous
Where is the origin of the extensor carpi ulnaris?
CEO
subcutaneous border of ulna
Where is the insertion of the extensor carpi ulnaris?
Base of 5th metacarpal
What is the function of the extensor carpi ulnaris?
Extends or adducts hand at the wrist
Which nerve supplies the extensor carpi ulnaris?
Posterior interosseous
What are the 5 muscles in the deep layer of the posterior compartment of the forearm?
Supinator Abductor pollicus longus Extensor pollicus brevis Extensor pollicus longus Extensor indicus
Where is the origin of the supinator
Supinator crest of ulna, distal to radial notch
Where is the insertion of the supinator?
lateral aspect of proximal shaft of radius
What is the function of the supinator?
Supination
Which nerve supplies the supinator?
Posterior interosseous
Where is the origin of the abductor pollicis longus?
Proximal dorsum of ulna
interosseous membrane
Dorsum of mid portion of radius
Where is the insertion of the abductor pollicis longus?
Lateral aspect of base of thumb metacarpal
What is the function of the abductor pollicis longus?
Abducts an extends thumb
Abducts wrist
Where is the origin of the extensor pollicis brevis?
dorsum of radius, adjacent to AbPL
adjacent part of interosseous membrane
Where is the insertion of the extensor pollicis brevis?
Base of proximal phalanx of the thumb
What is the function of the extensor pollicis brevis?
Extends thumb at metacarpophalangeal and carpometacarpal joints
Where is the origin of the extensor pollicis longus?
Dorsum of ulna, distal to AbPL
Adjacent part of interosseous membrane
Where is the insertion of the extensor pollicis longus?
Dorsum of base of terminal phalanx of thumb
What is the function of the extensor pollicis longus?
Extends metacarpophalangeal and interphalangeal joints of thumb
Extensor of wrist
Where is the origin of the extensor indicis?
Posterior aspect of ulna
interosseous membrane
Where is the insertion of the extensor indicis?
Dorsal expansion of index finger
