We mentioned earlier that many people, when they think of paralysis, think of a state in which the limbs experience a complete loss of movement or feeling. But chances are, you’ve heard your doctor refer to paralysis as either “complete” or “incomplete.” What is the difference between these two classifications, and what do they mean for the survivor?
Simply put, “complete” spinal cord injuries refer to any injury that results in the complete loss of function below the point of injury. An “incomplete” injury, on the other hand, refers to a spinal cord injury in which some feeling or movement is still evident below the point of injury.
Prompt Treatment is Crucial
The good news is that incomplete spinal cord injuries are more common than complete injuries, in large part because we now understand how important it is to immediately reduce swelling of the spinal cord following a spinal cord injury. The steps the survivor’s medical team immediately takes to reduce swelling quite often prevent further damage from occurring, allowing an injury to avoid the “complete” category. Incomplete injuries can vary greatly. They can result in some feeling but little or no movement, some movement but little or no feeling, and everything in between. The extent and severity of an incomplete injury can usually be safely determined about six to eight weeks following the injury, once spinal shock has subsided and the swelling has gone down.
Basic Types of Incomplete Paralysis
- Anterior cord syndrome is characterized by damage to the front of the spinal cord. This results in impaired movement, touch, pain, and temperature sensations below the point of injury. In most cases of anterior cord syndrome, some movement can later be recovered.
- Central cord syndrome results when the damage occurs to the center of the spinal cord. This results in loss of function in the arms, but some leg movement is preserved. Like anterior cord syndrome, some recovery is usually possible.
- Posterior cord syndrome is characterized by damage to the back of the spinal cord. Most survivors with posterior cord syndrome maintain good muscle power, pain, and temperature sensation, but experience poor coordination.
- Brown-Sequard syndrome results when one side of the spinal cord is damaged. The survivor experiences loss of movement but preserved sensation on one side of the body, while the other side of the body has loss of sensation but preserved movement.
- A cauda equina lesion is characterized by injury to the nerves located between the first and second lumbar region of the spine, resulting in partial or complete loss of sensation. In some cases, nerves are able to regenerate and function is recovered.
Classification of Spinal Cord Injury Severity
Many clinicians use the ASIA Impairment Scale to grade the severity of neurological loss. Almost every major organization associated with spinal cord injury has adopted the ASIA scale, and specialists at the hospital usually use the scale to assess the patient's level of injury.
- A = Complete: No motor or sensory function is preserved in the S4-S5 sacral segments
- B = Incomplete: Sensory function but not motor funciton is preserved below the neurological level and includes the S4-S5 sacral segments.
- C = Incomplete: Motor function is preserved below the neurological level, and more than half of key muslces below the neurological level have a muslce grade less than 3.
- D = Incomplete: Motor function is preserved below the neurological level, and at least half of key muscles below the neurological level have a muscle grade of 3 or more.
- E = Normal: Motor and sensory function are normal.