Spinal Cord Injuries

(SCIs ) SN. prepared

Oday Al-agha

Spinal Nerves

• There is a pair of spinal nerves at the level of each vertebrae for a total of 31 pairs

• Spinal nerves are named for the region from which they arise

• Spinal nerves are formed by the combination of the ventral and dorsal roots of the spinal nerve.

• Spinal nerves soon divide into ventral and dorsal rami (branches = rami )according to the area it supplies.

• The ventral rami in four regions unite to form plexuses (cervical ,brachial , lumber and sacral plexuses).

Spinal Nerves in the adult, the spinal cord is in the upper two thirds of the

spinal canal of the vertebral column. On transverse section, the spinal cord has an oval shape, and

the internal gray matter has the appearance of a butterfly or letter “H.”

The dorsal horns contain the IA neurons and receive afferent information from dorsal root and other connecting

neurons. The ventral horns contain the output association neurons

and lower motor neurons that leave the cord by the ventral roots.

Spinal Nerves

Thirty-two pairs (or 31) of spinal nerves(i.e., 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 2 or more coccygeal) are present.

Each pair communicates with it corresponding body segments

The spinal nerves and the blood vessels that supply the spinal cord enter the spinal canal through an intervertebral foramen.

Spinal Nerves After entering the foramen, they divide into two branches,

or roots : 1. one of which enters the dorsolateral surface of the cord

(i.e., dorsal root), carrying the axons of afferent neurons into the CNS.

2. Other root leaves the ventrolateral surface of the cord (i.e., ventral root), carrying the axons of efferent neurons into the periphery. These two roots fuseيندمج at the intervertebral foramen, forming the mixed spinal nerve.

Cross-section of vertebral column at the levelof the third thoracic vertebra, showing the meninges, the spinal

cord, and the origin of a spinal nerve and its branches or rami.

The Autonomic Nervous

(ANS) regulates, adjusts, and coordinates the visceral functions

of the body. The ANS, which is divided into the sympathetic

and parasympathetic systems, is an efferent system .It receives its afferent input from visceral afferent neurons.

The ANS has central nervous system and peripheral nervous system components.

Spinal cord injuries (SCIs)

• Damage to the spinal cord ranges from transient

concussion (patient recovers fully), to contusion, laceration, and compression of the cord

substance

• are a major health problem. • Most SCIs result from motor vehicle crashes.

Types and Classification of Spinal Cord Injury

• Alterations in body function that result from SCI depend on :

the level of injury (Tetra………)

the amount of cord involvement (complete or in..)

Clinical Manifestations

The consequences of SCI depend on the type and level of injury of the cord.Neurologic LevelThe neurologic level refers to the lowest level at which sensoryand motor functions are normal. Signs and symptomsincludethe following:• Total sensory and motor paralysis below the neurologic level.• Loss of bladder and bowel control (usually with urinaryretention and bladder distention).• Loss of sweating and vasomotor tone.• Marked reduction of BP from loss of peripheral vascularresistance.• If conscious, patient reports acute pain in back or neck;patient may speak of fear that the neck or back is broken.

Respiratory Problems

• Related to compromised respiratory function; severity

depends on level of injury.• Acute respiratory failure is the leading cause of

death inhigh cervical cord injury.

Assessment and Diagnostic Methods

• Detailed neurologic examination, x-ray examinations (lateral

• cervical spine x-rays), computed tomography (CT), magnetic

• resonance imaging (MRI), and ECG (bradycardia and asystole

• are common in acute spinal injuries) are common assessment

• and diagnostic methods.

Types and Classification of Spinal Cord Injury

the level of injury AS

A. Tetraplegia=sometimes referred quadriplegia

B. Paraplegia

C. Hemiparalysis

Tetraplegia

• impairment or loss of motor or sensory function (or both) after damage to neural structures in

• the cervical segments of the spinal cord.

• It results in impairment of function in the arms, trunk, legs, and pelvic organs

Paraplegia

• refers to impairment or loss of motor or sensory function (orboth) from damage of neural elements in the spinal

• canal in the thoracic, lumbar, or sacral segments of the spinal cord. With paraplegia, arm functioning is spared, but depending on the level of injury, functioning of the

• trunk, legs, and pelvic organs may be impaired.

• Paraplegia includes conus medullaris and cauda equinainjuries