What is Spinal Cord Injury?
A spinal cord injury (SCI) involves damage to the spinal cord and nerve roots. Car accidents, falls, violent acts, and non-traumatic disorders can injure the spinal cord. SCI temporarily or permanently stops or alters the ability of the brain to communicate with other parts of the body.
Paralysis is a common outcome (temporary or permanent). However, spinal cord injury involves much more than damage to the spinal cord. After the primary injury, a cascade of secondary events can occur, such as inflammation, that can amplify the effects of the injury. Those secondary events can also cause pain or other symptoms. Currently, there is intense research interest in this secondary response to injury.
According to the Spinal Cord Injury Information Network, approximately 40 cases per million population or 12,000 new cases occur each year in the United States1.
Facts about Spinal Cord Injury
- The spinal cord does not need to be severed (that's actually rare) to cause paralysis.
- Bruising of the spinal cord can cause paralysis.
- Insufficient blood flow to the spinal cord can damage it.
The severity of SCI depends on where the spinal cord is damaged and if the injury is complete or incomplete.
- Loss of all function (motor) and feeling (sensory) below the injury level
- Both sides of the body are equally affected
- Some function and feeling remains below the injury level
- One side of the body has more function or feeling than the other side
There are different types of incomplete spinal cord injury. Included are: anterior cord syndrome, central cord syndrome, and Brown-Séquard syndrome.
Anterior Cord Syndrome
The anterior spinal cord is the front section. Symptoms may be caused when this part of the cord is compressed by a bone fragment or when there is insufficient blood supply. Symptoms include functional (motor skills) and sensory loss (i.e., light touch, pinprick) below the injury level2.
Central Cord Syndrome
The central spinal cord is the middle area. These nerve fibers are large and exchange information between the spinal cord and the cerebral cortex (gray matter in the brain). The cerebral cortex is important to personality, interpreting sensation (feeling), and movement (motor function). The central spinal cord is important for hand and arm function, such as fine motor control (e.g., writing), although the lower body can be affected (e.g., loss of bladder control), too.
This syndrome affects one-half of the spinal cord, either the left or right side. If the right-hand side of the spinal cord is injured, symptoms affect the right side of the body (and if the left-hand side of the spinal cord is injured, the left side of the body is affected). It is characterized by partial loss of function or impaired function.
Spinal Levels and Areas Possibly Affected by SCI
|Spinal Level||Area||Pairs of Nerve Roots||Areas Possibly Affected|
|Cevical (C1 - C7)||Neck||8||Neck, arms, hands|
|Thoracic (T1 - T12)||Chest||12||Torso, arms|
|Lumbar (L1 - L5)||Low back||5||Hips, legs|
|Sacral (S1 - S5)||Pelvis||5||Groin, legs, toes|
|Coccyx||Tailbone||1||Skin covering tailbone, anus|
A note about interpreting the table: Remember that a complete SCI affects all spinal cord function below the injury. For example, a thoracic injury may start at the torso and arms level, but it will also affect the low back, pelvis, groin, tailbone, legs, and toes.