Key Muscles By Segmental Innervation

Question 1

Facial muscles, partial SCM, capital muscles

Answer 1

C1-C2

Question 2

SCM, partial diaphragm, upper traps

Answer 2

C3

Question 3

Diaphragm, partial deltoid, SCM, upper traps

Answer 3

C4

Question 4

Deltoid, biceps, rhomboids, brachioradialis, teres minor, infraspinatus

Answer 4

C5

Question 5

Extensor carpi radialis, pec major (clavicular), teres major, supinator, serratus anterior, weak pronator

Answer 5

C6

Question 6

Triceps, flexor carpi radialis, lats, pronator teres

Answer 6

C7

Question 7

Flexor carpi ulnaris, extensor carpi ulnaris, some hand intrinsics

Answer 7

C8

Question 8

Hand intrinsics, top half intercostals, pec major (sternal)

Answer 8

T1-T8

Question 9

Upper abdominals

Answer 9

T7-T9

Question 10

Lower abdominals

Answer 10

T9-T12

Question 11

Lower abdominals, weak quadratus lumborum

Answer 11

T12

Question 12

Iliopsoas, weak sartorius, weak adductors, weak rectus femoris

Answer 12

L2

Question 13

Sartorius, adductors, rectus femoris

Answer 13

L3

Question 14

Gluteus medius, TFL, hamstrings, tibialis anterior

Answer 14

L4

Question 15

Weak gluteus maximus, long toe extensor, tibialis posterior

Answer 15

L5

Question 16

Gluteus maximus, gastrocnemius, soleus

Answer 16

S1

Question 17

Anal sphincter

Answer 17

S2