Spinal Cord Trauma

American Spinal Injury Association (ASIA) Grading Scale for Spinal Cord Injury

A = No motor or sensory function preserved
B = Sensory but no motor function preserved
C = Nonuseful motor function preserved (less than antigravity strength)
D = Motor function preserved but weak
E = Normal motor and sensory function

Neurology Injury:

1. Complete Spinal Cord Injury (SCI)
2. Incomplete SCI
3. Specific Incomplete SCI syndromes:
a. Central Cord Syndrome
b. Brown-Sequard syndrome
c. Anterior Cord Syndrome
d. Conus medullaris Syndrome

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The Effects of Spinal Cord Injury.

The exact effects of a spinal cord injury vary according to the type and level injury, and can be organized into two types:

Complete SCI

There is no function below the level of the injury. Voluntary movement is impossible and physical sensation is impossible. Complete injuries are always bilateral, that is, both sides of the body are affected equally.

A person with an incomplete injury retains some sensation below the level of the injury. Incomplete injuries are variable, and a person with such an injury may be able to move one limb more than another, may be able to feel parts of the body that cannot be moved, or may have more functioning on one side of the body than the other. In addition to a loss of sensation and motor function below the point of injury, individuals with spinal cord injuries will often experience other changes.Bowel and bladder function is associated with the sacral region of the spine, so it is very common to experience dysfunction of the bowel and bladder. Sexual function is also associated with the sacral region, and is often affected. Injuries very high on the spinal cord (C-1, C-2) will often result in a loss of many involuntary functions, such as breathing, necessitating mechanical ventilators or phrenic nerve pacing. Other effects of spinal cord injury can include an inability to regulate heart rate (and therefore blood pressure), reduced control of body temperature, inability to sweat below the level of injury, and chronic pain and also incontinence. Physical therapy and orthopedic instruments (e.g., wheelchairs, standing frames) are often necessary, depending on the location of the injury.The Location of the InjuryKnowing the exact level of the injury on the spinal cord is important when predicting what parts of the body might be affected by paralysis and loss of function.Below is a list of typical effects of spinal cord injury by location (refer to the spinal cord map to the right). Please keep in mind that the prognosis of complete injuries are predictable, incomplete injuries are very variable and may differ form the descriptions below.Cervical injuriesCervical (neck) injuries usually result in full or partial tetraplegia. Depending on the exact location of the injury, one with a spinal cord injury at the cervical may retain some amount of function as detailed below, but are otherwise completely paralyzed.

C3 vertebrae and above: Typically lose diaphragm function and require a ventilator to breathe.
C4: May have some use of biceps and shoulders, but weaker.
C5: May retain the use of shoulders and biceps, but not of the wrists or hands.
C6: Generally retain some wrist control, but no hand function.
C7 and T1: Can usually straighten their arms but still may have dexterity problems with the hand and fingers. C7 is the level for functional independence. Thoracic injuriesInjuries at the thoracic level and below result in paraplegia. The hands, arms, head, and breathing are usually not affected.

T1 to T8 : Most often have control of the hands, but lack control of the abdominal muscles so control of the trunk is difficult or impossible. Effects are less severe the lower the injury.

T9 to T12 : Allows good trunk and abdominal muscle control, and sitting balance is very good. Lumbar and Sacral injuriesThe effect of injuries to the lumbar or sacral region of the spinal canal is decreased control of the legs and hips, and anus.

Central cord syndrome (picture 1)

is a form of incomplete spinal cord injury characterized by impairment in the arms and hands and, to a lesser extent, in the legs. This is also referred to as inverse paraplegia, because the hands and arms are paralyzed while the legs and lower extremities work correctly.Most often the damage is to the cervical or upper thoracic regions of the spinal cord, and characterized by weakness in the arms with relative sparing of the legs with variable sensory loss.This condition is associated with ischemia, hemorrhage, or necrosis involving the central portions of the spinal cord (the large nerve fibers that carry information directly from the cerebral cortex). Corticospinal fibers destined for the legs are spared due to their more external location in the spinal cord.This clinical pattern may emerge during recovery from spinal shock due to prolonged swelling around or near the vertebrae, causing pressures on the cord. The symptoms may be transient or permanent.

Anterior Cord Syndrome (picture 2)

is also an incomplete spinal cord injury. Below the injury, motor function, pain sensation, and temperature sensation is lost; touch, propioception (sense of position in space), and vibration sense remain intact. Posterior Cord Syndrome (not pictured) can also occur, but is very rare.

Brown-Sequard Syndrome (picture 3)

usually occurs when the spinal cord is hemisectioned or injured on the lateral side. On the ipsilateral side of the injury (same side), there is a loss of motor function, propioception, vibration, and deep touch. Contralaterally (opposite side of injury), there is a loss of pain, temperature, and light touch sensations.