Brachial Plexus muscles Flashcards
Trapezius
Action: Upper scapular elevator,
Mid: scap retraction
Lower: scapular depression
Inn: CN 11
Lattisimus Dorsi
A: Shoulder ext, Add, IR humerus
I: Thoracodorsal n
Levator Scap
A: elevates the scap
I: dorsal scap n
Deltoid
A: Ant: flexor: IR (clavicular head)
Med: Abd+ ER
I: Axillary n
Supraspinatus
A: shoulder abd first 15 degrees- helps with humeral compression in glenoid
I: Suprascapular n
Infraspinatus
A: shoulder ER; helps to stabilize humeral head in glenoid
I: Suprascapular n
Teres minor
A: ER+ humeral compression
I: Axillary n
Teres Major
A: IR
I : subscap n (lower)
Subscapularis
A: IR; prevents anterior displacement of humerus
I: upper and lower subscap n
Pectoralis Major
A: Shoulder IR, horiz ADD, flexor
I: medial and lateral pec n
Biceps Brachii
A: Elbow flexor, supinator, shoulder flexor
I: Musculocutaneous n
Brachialis
A: elbow flexor
I: musculocutaneous n (small cont from radial n)
Corachobracialis
A: flexes and add arm at the shoulder
I: musculocutaneous n
Triceps and anconeus
A: elbow ext (Long head extends shoulder too)
I: Radial N
Pronator teres/quadratus
A: pronation, weak elbow flexor
I: Median N
Flexor Carpi Radialis
A: wrist flexion, radial dev
I: Median N
Palmaris Longus
A: wrist flexion
I: Median N
Flexor carpi Ulnaris
A: Wrist flexion, ulnar dev
I: Ulnar N
Flexor digitorum superficalis
A: Finger flexor to PIP, weak wrist, MCP and elbow flexion
I: Median n
Flexor digitorum profundis
A: Flexor to DIP
I : Ulnar and Anterior interosseus branch of Median N
Flexor Pollicus Longus
A: Thumb flexion
I: Median (interosseus branch)
Supinator
A: supinates forearm
I: Radial N
Brachioradialis
A: elbow flexor in mid pronation
I: Radial N
Extensor Carpi radialis longus
A: wrist ext+ rad dev
I: Radial N
Extensor carpi radialis brevis
A: wrist ext+ rad dev
I: Radial n
Extensor digitorum
A: MCP and PIP ext; wrist ext when fingers ext
I: radial N (posterior interosseus)
Extensor Digiti Minimi
A: Ext of 5th MCP+ IP; wrist ext when fingers ext
I: Radial N (posterior interosseus branch)
Extensor carpi ulnaris
A: wrist ext and ulnar dev
I: Radial N (posterior interosseus branch)
Extensor Indicis
A: extends 2nd MCP, 22 wrist ext
I: Radial n (posterior interosseus branch)
Extensor pollicus longus
A: extends hallux at MCP and IP joints, can also abd hallux
I: radial n (posterior interosseus branch)
Extensor pollicis brevis
A: extends hallux at MCP jt
I: Radial n (posterior interosseus branch)
Abductor pollicis longus
A: thumb abd, ext, ER
I : Radial nerve (posterior interosseus branch)
