1. Nervous system
SHANDONG UNIVERSITY Liu Zhiyu

2. 一、Divisions of nervous system
Ⅰ) Central nervous system (CNS)
Cerebellum
Telencephalon
Diencephalon
Brain stem
Spinal cord
Brain
Pons
Midbrain
Medulla oblongata
CNS

3. Ⅱ) Peripheral nervous system (PNS)
Cranial n. (12 pairs)
Spinal n. (31 pairs)
PNS
Visceral n.
Somatic nerve
Somatic sensory n.
Somatic motor n.
Visceral motor n.
Visceral sensory n.
Sympathetic part
Parasympathetic part

4. Bipolar neuron I. Essential strunctures Neurons of nervous system
cell body
Dendrites
Axon
Neurons
Nuroglia:
glial cell
Bipolar neuron
Pseudounipolar neuron
Multipolar neuron
Ⅰ) Structural classification
central branch
peripheral branch

5. Ⅱ) Functional classification
Afferent (sensory) neuron Efferent (motor) neuron Association neuron (interneuron)

6. Nerve fiber myelinated nerve fiber unmyelinated nerve fiber

7. II、reflex reflex arc
Reflex: a reaction of the organism by the nervous system in response to a stimulus
Reflex arc: consist of 5 basic components
afferent neuron
receptor
centre
efferent neuron
effector

8. Spinal nerves Formation:
each spinal nerve is formed by union of anterior and posterior roots at intervertebral foramen
The anterior root contains motor fibers for skeletal muscles.
The posterior rootcontains sensory fibers whose cell bodies are in the spinal ganglion

9. Spinal nerves Spinal ganglia
is an enlargement of the posterior root near the intervertebral foramen which consist of the bodies of pseudounipolar neurons

10. Divisions of spinal nerves:
cervical nerves 8对
thoracic nerves 12对
lumbar nerves 5对
sacral nerves :5对
coccygeal nerve : 1对

11. The fiber components of spinal cors
There are four types of fibers contained in the spinal n.
Somatic afferent (sensory) nerve fibers : Visceral afferent (sensory) nerve fibers
Somatic efferent (motor) nerve fibers ：
Visceral efferent (motor) nerve fibers ：

12. branches of spinal nerves
Each spinal n. is divided into 4 branches after leaving the intervertebral foramen immediately
anterior branche
posterior branche
meningeal branch
communicating branc

13. cervical plexus branchial plexus lumbar plexus sacral plexus 。
posterior branche
anterior branche ：，
cervical plexus
branchial plexus
lumbar plexus
sacral plexus 。

14. Formation ： 二、cervical plexus Branches： Muscular brnches
it consists of the anterior rami of C1-C4 nerves.
Branches：
Cutaneous branches
Muscular brnches
   

15. Branches Cutaneous branches: Lesser occipital Great auricular
Transverse nerve of neck
Supraclavicular nerves
They emerge around middle of posterior border of sternocleidomastoid, to supply skin of neck and scalp between auricle and external occipital protuberance

16. Phrenic nerve arises from the of C3-C5,
Muscular branches:
supply the deep muscles of neck
Phrenic nerve arises from the of C3-C5,
innervation to diaphragm;

17. Phrenic nerve
Sensory fibers supply to pleurae, pericardium and peritoneum of diaphragm; usually right phrenic nerve may be distributed on live, gallbladder and biliary system.

18. 二、 brachial plexus
Formation ：
Formed by anterior rami of C5-C8 and T1 nerves
Position ：
Passes through the scalene fissure (斜角肌间隙) to posterosuperior of subclavian artery, then enters the axilla to form three cords(束) which around the axillary atery.
Medial cord 、
Lateral cord
Posterior cord

19. 二、 brachial plexus Branches Median nerve Musculocutaineous nerve
Ulnar nerve
Axillary nerve
Radial nerve

21. Anterior branche of thoracic nerve，
Intercostal nerves （T1-T11），
Subcostal nerve（T2） ，。
Distribution:
intercostales
anterolateral abdominal muscles
skin of thoracic and abdominal wall, parietal pleura and peritoneum

22. Anterior branches of thoracic nerves
The distribution of the anterior branches of the thoracic n. is segmental.
T2 Sternal angle
T4 Nipple
T6 Xiphoid process
T8 Costal arch
T10 Umbilicus
T12 Midpoint between umbilicus and symphysis pubis

23. position ：lies behind the psoas major and beside the lumbar vertera
四、lumbar plexus
Formation:
anterior rami of L1-L3,
a part of anterior rami of T12 and L4
position ：lies behind the psoas major and beside the lumbar vertera

24. branches： Femoral Obturator Cutaneous Genitofemoral Iliohypogastric
Ilioinguinal
Lateral femoral

25. Femoral n. disribution route：
Runs downward and laterally between psoas major and iliacus, passes deep to inguinal ligament;
disribution
muscular branches---supplies anterior thigh muscles (quadricep肌,sartorius and pectineus),

26. Femoral n. sensory branches---
hip and knee joint, and skin on anteromedial side of thigh,
saphenous nerve is distributed to skin of medial side of leg and foot

27. Obturator Route： Enters thigh through obturator foramen; Distribution：
muscular branches--- supplies medial group of muscles of thigh, obturator externus,
sensory branches--- skin of medial side of thigh

28. Lateral femoral cutaneous
It arises from the lateral border of the psoas major and runs inferolateral to enter the thigh posterior to the inguinal lig.,just medial to the anterior superior iliac spine. it distribute to the skin over the lateral aspect of the thigh.

29. Genitofemoral
It pierces the anterior surface of the psoas major and runs inferiorly ,and divide into femoral and genital branches
The femoral branche distribute to the skin over the femoral triangle; and the genital branche distribute to the scrotum(greater lip of pudendum)

30. 五、 sacral plexus formation ：
formed by anterior rami of L4 and L5 spinal nerves (the lumbrosacral trunk) and anterior rami of sacral and coccygeal nerves
Position:
lies in pelvic cavity, anterior to sacrum and piriformis

31. 五、 sacral plexus main branches Inferior glureal n. Sciatic nerve
main branches
Sciatic nerve
Pudendal nerve
Superior gluteal n.
Inferior glureal n.

32. Sciatic nerve
Leaves pelvis through infrapiriform foramen to enter gluteal region,
runs inferiorly deep to gluteus maximus, passing midway between the greater trochanter of femur and ischial tuberosity to back of thigh, lying deep to long head of biceps femoris,
normally divided into tibial and common peroneal nerves just above popliteal fossa;

33. Sciatic nerve it innervates semitendinosus Semimembranosus
and biceps femoris

34. Tibial nerve
Decends through popliteal fossa , then runs inferiorly with posterior tibial vessels and dividing into medial and lateral plantar nerves behind the medial malleolus; supplies posterior muscles of leg and knee joint

35. Common peroneal nerve
Arises at apex of popliteal fossa and follows medial border of biceps femoris and its tendon; passes over posterior aspect of head of fibula and then winds around neck of fibula, deep to peroneus longus, where it divides into deep and superficial peroneal nerves,to supply the anterior and lateral groups m. of the leg.

36. Superficial peroneal
Deep peroneal