Muscles that Move Joints
| Muscle | Nerve | Segmental Innervation | Function | |
|---|---|---|---|---|
| Shoulder | Supraspinatus | Suprascapular n. | C5,6 | Abduction of upper arm |
| Deltoid | Axillary n. | C5,6 | Abduction of upper arm | |
| Forearm | Biceps | Musculocutaneous n. | C5,6 | Flexion of the supinated forearm |
| Brachioradialis | Radial n. | C5,6 | Forearm flexion with arm between pronation and supination | |
| Triceps | Radial n. | C6,7,8 | Extension of forearm | |
| Ext. carpi radialis | Radial n. | C5,6 | Extension and abduction of hand at the wrist | |
| Ext. carpi ulnaris | P. interosseous n. | C7,8 | Extension and adduction of hand at the wrist | |
| Ext. digitorum | P. interosseous n. | C7,8 | Extension of fingers at the MCP joints | |
| Supinator | P. interosseous n. | C6,7 | Supination of the extended forearm | |
| Flex. carpi radialis | Median n. | C6,7 | Flexion and abduction of hand at the wrist | |
| Flex. carpi ulnaris | Ulnar n. | C7,8,T1 | Flexion and adduction of hand at the wrist | |
| Pronator teres | Median n. | C6,7 | Pronation of the forearm | |
| Wrist | Ext. carpi ulnaris | Ulnar n. | C7,8,T1 | Extension/adduction at the wrist |
| Flex. carpi radialis | Median n. | C6,7 | Flexion/abduction at the wrist | |
| Hand | Lumbricals | Median + ulnar n. | C8,T1 | Extension of fingers at PIP joint with the MCP joint extended and fixed |
| Interossei | Ulnar n. | C8,T1 | Abduction/adduction of the fingers | |
| Flex. digitorum | Median + A. interosseous n. | C7,C8,T1 | Flexion of the fingers | |
| Thumb | Opponens pollicis | Median n. | C8,T1 | Touching the base of the 5th finger with thumb |
| Ext. pollicis | P. interosseous n. | C7,8 | Extension of the thumb | |
| Add. pollicis | Ulnar n. | C8,T1 | Adduction of the thumb | |
| Abd. pollicis | Median n. | C8,T1 | Abduction of the thumb | |
| Flex. pollicis br. | Ulnar n. | C8,T1 | Flexion of the thumb | |
| Thigh | Iliopsoas | Femoral n. | L1,2,3 | Flexion of the thigh |
| Glutei | Sup. + inf. gluteal n. | L4,L5,S1,S2 | Abduction, extension, and internal rotation of the leg | |
| Quadriceps | Femoral n. | L2,3,4 | Extension of the leg at the knee | |
| Adductors | Obturator n. | L2,3,4 | Adduction of the leg | |
| Hamstrings | Sciatic n. | L5,S1,S2 | Flexion of the leg at the knee | |
| Foot | Gastrocnemius | Tibial n. | S1,S2 | Plantar flexion of the foot |
| Tibialis ant. | Deep peroneal n. | L4,5 | Dorsiflexion of the foot | |
| Peronei | Deep peroneal n. | L5,S1 | Eversion of the foot | |
| Tibialis post. | Tibial n. | L4,5 | Inversion of the foot | |
| Toes | Ext. hallucis l. | Deep peroneal n. | L5,S1 | Dorsiflexion of the great toe |
Abbreviation: MCP, metacarpophalangeal; PIP, proximal interphalangeal.