1. SPINAL NERVES
Dr. Enis CEZAYİRLİ

2. MOTOR FIBERS Right and left cortices Fibrae corticospinales
Capsula interna
Crus cerebri
Decussatio pyramidum
Somatomotor anterior

3. LOWER (SECOND) MOTOR NEURON
The neuron in the cortex and its axon is referred to as
UPPER (FIRST) MOTOR NEURON
Somatomotor neuron in the cornu anterior of medulla spinalis and its peripheral axon is referred to as
LOWER (SECOND) MOTOR NEURON

4. MEDULLA SPINALIS SEGMENTS
8 cervical+12 thoracic+5 lumbar +5 sacral+1 (3) coccygeal
Each segment except last 2 coccygeal has 1 pair spinal nerve
Spinal nerve of C1 segment (=C1 spinal nerve) passes between os occipitale and Atlas
Cauda equina

5. SPINAL NERVE Fila radicularia (rootlet)
Rootlets form radices within Canalis vertebralis
Radix motoria (anterior)
(=anterior root)
Radix sensoria (posterior)
(=posterior root)

6. SPINAL NERVE ganglion spinale on Radix posterior Radix motoria +
Radix sensoria =
N. spinalis
N. spinalis divides into Ramus anterior and Ramus posterior

7. METAMERE-MYOTOME-DERMATOME
Metamere: All structures supplied by a spinal nerve
Myotome: Muscles supplied by a spinal nerve
Dermatome: Region of skin supplied by a spinal nerve
A dermatome can be supplied by more than one spinal nerve

8. DERMATOMLAR
Axial
line C5

9. PLEXUS CERVICALIS
Formed by the anterior branches of first 4 cervical spinal nerves at the level of the first 4 cervical vertebrae, deep to v. jugularis interna and m. sternocleidomastoideus

10. PLEXUS CERVICALIS
Four sensory branches of Pl. cervicalis emerge at Punctum nervosum
Punctum nervosum: Mid-point of the posterior border of M. sternocleidomastoideus
N. occipitalis minor
N. auricularis magnus
N. transversus colli
Nn. supraclaviculares

11. Muscles supplied by Pl. cervicalis
M. rectus capitis anterior and lateralis
M. longus colli and capitis
M. geniohyoideus
M. thyrohyoideus
M. omohyoideus (both bellies)
M. sternohyoideus
M. sternothyroideus
Diaphragm (n. phrenicus)
M. sternocleidomastoideus (via n. accessorius)
M. trapezius (via n. accessorius)
M. levator scapulae (via n. dorsalis scapulae)
M. scalenus medius

12. PLEXUS BRACHIALIS
Formed by the anterior branches of C5-T1 spinal nerves
Small twigs from anterior branches of C4 and T2 spinal nerves also join the plexus.
Anterior branches of spinal nerves pass between m. scalenus anterior and medius and become superficial
Then pass beneath clavicula to enter fossa axillaris
Then pass beneath clavicula and ??? to enter fossa axillaris

13. PLEXUS BRACHIALIS
C5 + C6 + Twigs from C4 join to form truncus superior
C7 forms truncus medius
C8 + T1 + twigs from T2 join to form truncus inferior

14. PLEXUS BRACHIALIS
The trunks split into anterior and posterior divisions
Posterior divisions of all trunks form fasciculus posterior
Anterior divisions of Truncus superior and medius join to form fasciculus lateralis
Anterior division of Truncus inferior forms fasciculus medialis
Fascicles are named according to their position with respect to a. axillaris

15. N. AXILLARIS
Passes through Spatium axillare laterale alongside a. and v. circumflexa humeri posterior
Winds around Collum chirurgicum

16. N. AXILLARIS Supplies M. deltoideus and m. teres minor
Supplies the deltoid region

17. N. RADIALIS Largest branch of Plexus brachialis
Winds around from the medial to the lateral side of the humerus in sulcus nervi radialis in company with a. profunda brachii

18. N. RADIALIS
Supplies the skin on the dorsal surface of the arm, dorsomedial surface of the forearm, dorsal surface of lateral 3.5 fingers (except distal phalanges)

19. Muscles supplied by N. radialis
M. triceps brachii
M. brachioradialis
M. extensor carpi radialis longus and brevis
M. extensor carpi ulnaris
M. anconeus
M. supinator
M. abductor pollicis brevis
Extensor muscles of the fingers

20. N. MUSCULOCUTANEOUS
Supplies M. coracobrachialis, m. biceps brachii and m. brachialis
Supplies the lateral, anterolateral and posterolateral surfaces of the forearm

21. N. MEDIANUS
Runs alongside a. brachialis and n. ulnaris on the medial aspect of the arm
Does not give off any branch in the arm
Passes through canalis carpi to reach the palm

22. N. MEDIANUS
Supplies the skin on the palmar surface of lateral 3.5 fingers and dorsal surfaces of the distal phalanges of lateral 3.5 fingers

23. Muscles supplied by N. MEDIANUS
M. flexor digitorum superficialis
M. flexor digitorum profundus (except ulnar part of the muscle)
M. flexor pollicis longus
Superficial head of M. flexor pollicis brevis
M. flexor carpi radialis
M. pronator quadratus
M. pronator teres
M. palmaris longus
M. abductor pollicis brevis
M. opponens pollicis
1st and 2nd lumbrical muscles

24. N. ULNARIS Runs in company with a. brachialis and n. medianus
Passes in sulcus nervi ulnaris behind epicondylus medialis of humerus

25. N. ULNARIS
Supplies the skin of the dorsal and palmar surfaces of medial 1.5 fingers

26. Muscles supplied by N. ULNARIS
M. flexor carpi ulnaris
M. flexor digitorum profundus (ulnar part of the muscle only)
M. palmaris brevis
Hypothenar muscles (m. abductor digiti minimi, m. flexor digiti minimi brevis and m. opponens digiti minimi)
3rd and 4th lumbrical muscles
All interosseal muscles
M. adductor pollicis
Deep head of m. flexor pollicis

27. PLEXUS LUMBALIS L1
Formed by anterior branches of L1-3 spinal nerves + twigs from L4 (+sometimes twigs from T12) on the deep surface of the posterior abdominal wall

28. PLEXUS LUMBALIS Supplies the skin of the medial-lateral gluteal region
Regio hypogastrica
External genitalia
Lateral surface of the thigh

29. Muscles supplied by the branches of Pl. lumbalis
M. obliquus internus abdominis
M. transversus abdominis

30. N. OBTURATORIUS
Enters canalis obturatorius

31. N. OBTURATORIUS Supplies hip and knee joints
Supplies medial aspect of the mid-lower thigh

32. Muscles supplied by N. OBTURATORIUS
M. adductor longus
M. gracilis
M. adductor brevis
M. obturator externus
M. adductor magnus

33. N. FEMORALIS Descends between m. psoas major and m. iliacus
Passes through Lacuna musculorum

34. N. FEMORALIS
Supplies the skin of anterior and medial aspects of the thigh
Medial aspects of the leg and ankle (via its n. saphenus branch)

35. Muscles supplied by N. FEMORALIS
M. iliacus
M. pectineus
M. sartorius
M. quadriceps femoris

36. PLEXUS SACRALIS
Formed by twigs from L4-5 and anterior branches of S1-3 spinal nerves

37. PLEXUS SACRALIS
Supplies the perineum, posterior surfaces of the thigh and leg

38. Muscles supplied by the branches of Pl. sacralis
M. gluteus maximus
M. gluteus medius
M. gluteus minimus
External rotators of the thigh

39. N. ISCHIADICUS Largest nerve of the body Deep to m. gluteus maximus
Usually lies in the inferior-medial quadrant of the hip

40. N. ISCHIADICUS Descends in the middle of the thigh
Gives off its terminal branches n. tibialis and n. peroneus communis near or in Fossa poplitea

41. N. ISCHIADICUS Supplies the hip joint
Supplies motor fibers to ischiocrural muscles
m. semitendinosus
m. semimembranosus
m. biceps femoris

42. N. TIBIALIS
Descends on the posterior aspect of the leg, between superficial and deep flexor muscles towards malleolus medialis

43. N. TIBIALIS
Supplies the supero-lateral aspect of the leg, heel and almost all of the sole of the foot
???

44. Muscles supplied by N. TIBIALIS
All flexor muscles on the back of the leg:
M. triceps surae
M. popliteus
M. plantaris
M. tibialis posterior
M. flexor digitorum longus
M. flexor hallucis longus

45. N. PERONEUS COMMUNIS Winds around collum fibulae.
Divides into n. peroneus superficialis and profundus

46. N. PERONEUS PROFUNDUS
N. peroneus
profundus

47. Muscles supplied by N. PERONEUS PROFUNDUS
M. tibialis anterior
M. extensor digitorum longus
M. peroneus tertius
M. extensor hallucis longus
M. extensor digitorum brevis
1st and 2nd dorsal interosseal muscles

48. N. PERONEUS SUPERFICIALIS

49. Muscles supplied by N. PERONEUS SUPERFICIALIS
M. peroneus longus
M. peroneus brevis