Ch.13 the spinal cord, spinal nerves, and somatic reflexes

Epidural

Contains blood vessels, areolar connective tissue, and fat; anesthesia injection

Subdural

Serous fluids

Subarachnoid

CSF and blood vessels within web-like strands of arachnoid tissue

First order neuron

Detects stimulus and transmits signals to spinal cord or brainstem

Second order neuron

Continues to the thalamus at the upper end of the brainstem

Third order neuron

Carries the signal the rest of the way to the sensory region of the cerebral cortex

Upper motor neuron

Originates in cerebrum cortex or brainstem and terminates on a lower motor neuron

Lower motor neuron

Cell body is in brainstem or spinal cord; axon leads to muscle or other target organ

Posterior/ dorsal root

Sensory input to spinal cord

Anterior / ventral root

Motor input out of spinal cord

Posterior/dorsal ramus

Innovate deep muscles of the trunk responsible for movements of the vertebral column and the connective tissue and skin near the midline of the back

Anterior/ ventral ramus

Intervention according to part of spinal cord of organ

Thoracic region

From intercostal nerves that innovate intercostal muscle and skin over thorax

Communicating rami

Communicate with sympathetic chain of ganglia

Radial nerve

Cs-C8, T1; triceps brachii, anconeus, brachioradialis, und extensor muscles of forearm; movements at elbow, and wrist and thumbs; skin of posterior surface of arm and forearm, lateral 2/3 of dorm of hand

Musculocutaneous nerve

C5 -C7; lateral cord of brachial plexus; motor: coracobrachialis, biceps brachii, brachialis; movements at shoulder, elbow, and wrist I skin of lateral surface of forearm

Ulnar nerve

C8,T1 (+-C7); medial cord; movements at wrist fingers, hand; skin of medial 1/3 of hand, little linger, and medial ½ of ring finger

Median nerve

C6-C7, lateral and C8-T1, medial; motor: flexor muscles of forearm and five hand muscles; skin of lateral 2/3 palm, thumb, index and middle fingers; lateral ½ of ring finger and dorsal tips of same fingers

Carpel tunnel syndrome

Median nerve compression at the volar/palmer aspect of the wrist causes symptoms of numbness, tingling, pain, and weakness in the hand and forearm

Pectoral

Pectoralis major and minor

Long thoracic

Serratus anterior

thoracodorsal

Latissimus dorsi

Subscapulcer

Subscapularis, teres major

Suprascapular

Supraspinatus, infraspinatus

Obturator nerve

L2-L4; rotates thigh medically, ad ducts thigh, flexes knee; skin of superior middle side of thigh

Femoral nerve

L2-L4; flexes hip and knee, extends knee; skin of anterior and lateral thigh, medial leg and foot

Sciatic nerve

Leg flextion at the knee, the hamstring muscles before divided into the tibias common peroneal nerve

Tibial nerve

Extends hip, flexes knee and toes, planter flexes foot, adduces thigh

Fibular (perineal) nerve

Extends his and flexes knee; skin of internal and anterior leg and dorsum of foot

Withdrawl reflex with reciprocal innervation

Causes relaxation of extensor muscle when flexor muscle contracts

Withdraws reflex with crossed extensor reflex

When a withdrawal reflex is initiated in one lower limb, the crossed extensor reflex causes extension of opposite lower limb