Spinal Cord Injury

Potential Causes of Spinal Cord Dysfunction

• Injuries that narrow the space for the spinal cord: broken bones in your back or neck and torn ligaments that cause vertebrae to move in different directions.
• Diseases that affect the bones and joints and compress the cord: arthritis, osteoporosis, stenosis, spondylolisthesis, and cancer
• Motor vehicle accidents (37%)
• Acts of violence (28%): gunshot wounds, stab wounds, and fragments from explosions
• Falls (21%)
• Infections
• Tumors near the spine that compress the spinal cord
• Blocked blood supply to the spinal cord which causes death of the tissue

Risks

• Gender : majority (up to 82%) are male
• Age: more than 50% of injuries occur between the ages of 16 to 30
• Sports related:  gymnasts, skiers, hockey players, divers, and surfers

American Spinal Injury Association (ASIA)

• Developed International Standards for Neurological Classification of Spinal Cord Injury.
• The level of injury to the spinal cord is numbered based on the lowest level of the spinal cord which continues to function normally.
• The level of the spinal cord injury is not always the same as the level where the injury occurred.
• Assists in determining whether the injury is complete or incomplete.
• It is important to your rehabilitation that you know and understand your level of injury. 

Types and Levels of Injury

Tetraplegia (Formally referred to as Quadriplegia)

• Spinal cord injury that is at the cervical level, C1-C8 (in the neck).
• The cervical nerve roots supply messages to the arms and hands and muscles that control breathing.
• Numbness and weakness occurs in the arm and hands, breathing may be more difficult.
• Everything below the level of the injury is effected including the trunk and legs.

Paraplegia

• Spinal cord injury that is at a thoracic, lumbar, or sacral level.
• These levels supply messages to the trunk and legs. Arm function is spared.
• Numbness and weakness or loss of movement and sensation occurs below the level of injury.

Complete SCI

• No voluntary movement and no feeling exists below the level of injury.
• Absent sensory and motor function in the lowest sacral segment (S5 the peri-anal area).

Incomplete SCI

• Only partial damage occurred to the spinal cord allowing some nerve fibers to still be intact.
• Some voluntary movement and feeling is present below the level of injury and in the lowest sacral segment (S5).

Anterior Cord Syndrome

• Injury to the motor and sensory pathways in the anterior portion of the spinal cord.
• Loss of ability to feel pain and changes in temperature.

Central Cord Syndrome

• Damage to the large nerve fibers that carry information directly from the cerebral cortex (brain) to the spinal cord.
• May cause paralysis and/or loss of fine control of movements in the arms and hands with less impairment of the legs.
• Sensory loss below the site of injury and loss of bladder control may occur.
• Amount and type of functional loss is related to the severity of damage to the nerves of the spinal cord.

Posterior Cord Syndrome

• Typically occur with presence of a tumor or spinal artery infarct
• Loss of motor function
• Loss of proprioception, vibration, and two point discrimination
• This type of injury is very rare

Brown-Sequard Syndrome

• Damage to the right or left half of the spinal cord that causes paralysis on the same side of the injury.
• Loss of pain and temperature on the opposite side of the injury
• Loss of ability to sense position, loss of deep touch and vibration on side of injury. 

Conus Medullaris

• Injury at the terminal end of the spinal cord and lumbar nerve roots below the L1 vertebrae.
• Sacral segments may show preserved reflexes.
• Bowel and bladder function may be spastic or flaccid based on the nerves injured.

Cauda Equina

• Injury that occurs in the lumbosacral nerve roots.
• Areflexic bowel,  bladder, and legs.

Upper Motor Neuron Injury

• Occurs with complete injuries.
• Connection between the brain and the body below the level of injury is disrupted.
• LMNs remain intact and continue to carry out reflex actions (without limits set by brain) so spasticity occurs.

Lower Motor Neuron Injury

• At the lower tip of the spinal cord (cauda equina).
• Causes impaired reflex actions.
• Muscles no longer have nerve contact to stimulate them so spasticity does not occur.

Spinal Concussion

• Caused by a sudden, violent jolt that injures the tissues around the spinal cord.
• Can be complete or incomplete
• Generally resolves within one or two days. 

Spinal Contusion (Bruise)

• Bleeding occurs in the spinal column which can cause death of the neurons.
• May produce symptoms including: numbness, tingling, electric shock-like sensations, and burning in the arms and legs.
• Symptoms may or may not resolve.