Other commentsSign in to post comments. You don't have an account? Sign up now!
Related posts
Bloolad donorDeep peroneal nerveDiagnosis?Diagnosis?Diagnosis?If you believe in it and it makes you happy, never stop fighting for it!🥊🩺Cranial nervesOverview of Spinal Cord
• Information highway between brain and body
• Extends through vertebral canal from
foramen magnum to L1
• Each pair of spinal nerves receives sensory
information and issues motor signals to
muscles and glands
• Spinal cord is a component of the Central
Nervous System while the spinal nerves are
part of the Peripheral Nervous System
Functions of the Spinal Cord
• Conduction
– bundles of fibers passing information up and down
spinal cord
• Locomotion
– repetitive, coordinated actions of several muscle
groups
– central pattern generators are pools of neurons
providing control of flexors and extensors (walking)
• Reflexes
– involuntary, stereotyped responses to stimuli
(remove hand from hot stove)
– involves brain, spinal cord and peripheral nerves
Anatomy of the Spinal Cord
• Cylinder of nerve tissue within the vertebral
canal (thick as a finger)
– vertebral column grows faster so in an adult the spinal
cord only extends to L1
• 31 pairs of spinal nerves arise from cervical,
thoracic, lumbar and sacral regions of the cord
– each cord segment gives rise to a pair of spinal
nerves
• Cervical and lumbar enlargements
• Medullary cone (conus medullaris) = tapered tip
of cord
• Cauda equinae is L2 to S5 nerve roots resemble
horse’s tail
Meninges of the Spinal Cord
• 3 Fibrous layers enclosing spinal cord
• Dura mater
– tough collagenous membrane surrounded by
epidural space filled with fat and blood vessels
• epidural anesthesia utilized during childbirth
• Arachnoid mater
– layer of simple squamous epithelium lining dura
mater and loose mesh of fibers filled with CSF
(creates subarachnoid space)
• Pia mater
– delicate membrane adherent to spinal cord
– filium terminale and denticulate ligaments anchor
the cord
Nerve Plexuses
• Ventral rami branch and anastomose repeatedly
to form 5 nerve plexuses
– cervical in the neck, C1 to C5
• supplies neck and phrenic nerve to the diaphragm
– brachial in the armpit, C5 to T1
• supplies upper limb and some of shoulder and neck
– lumbar in the low back, L1 to L4
• supplies abdominal wall, anterior thigh and genitalia
– sacral in the pelvis, L4, L5 and S1 to S4
• supplies remainder of lower trunk and lower limb
– coccygeal, S4, S5 and C0Nerve injury mn DrCuMaAmyloidosis
