Spine Disorders
SIGNS AND SYMPTOMS The signs and symptoms of a spinal cord injury depend on the location of the injury and the severity of the injury. Injuries which involve the upper portion of the spinal cord have the potential to cause a greater degree of paralysis than injures involving lower portions. Spinal cord injuries are classified as either partial (incomplete) or complete, depending on the extent of the cross sectional injury. With an incomplete spinal cod injury the spinal cord able to carrying some messages between the brain/brainstem and the body. This results in retention of some ability to perceive sensory stimuli below the injury and some muscle function below the level of injury. A complete spinal cord injury is defined as a complete loss of motor (muscle) function and a loss of the ability to perceive sensory stimuli below the area of injury. Sometimes specialists will refer to a complete spinal cord injury when there is in fact minimal preservation of nerve pathways as the spinal cord is not completely cut in half. Incomplete spinal cord injuries may be associated with some recovery whereas those diagnosed with complete spinal cord injury rarely expertise significant recovery. Spinal cord injuries may result in one or more of the following signs and symptoms:
CAUSES
A spinal cord injury usually begins with a sudden, traumatic blow to the spine that fractures or dislocates vertebrae. The damage begins at the moment of injury when displaced bone fragments, disc material, or ligaments bruise or tear into spinal cord tissue. Axons are cut off or damaged beyond repair, and neural cell membranes are broken. Blood vessels may rupture and cause heavy bleeding in the central grey matter, which can spread to other areas of the spinal cord over the next few hours. Within minutes, the spinal cord swells to fill the entire cavity of the spinal canal at the injury level. This swelling cuts off blood flow, which also cuts off oxygen to spinal cord tissue. Blood pressure drops, sometimes dramatically, as the body loses its ability to self-regulate. As blood pressure lowers even further, it interferes with the electrical activity of neurons and axons. All these changes can cause a condition known as spinal shock that can last from several hours to several days. Although there is some controversy among neurologists about the extent and impact of spinal shock, and even its definition in terms of physiological characteristics, it appears to occur in approximately half the cases of spinal cord injury, and it is usually directly related to the size and severity of the injury. During spinal shock, even undamaged portions of the spinal cord become temporarily disabled and can't communicate normally with the brain. Complete paralysis may develop, with loss of reflexes and sensation in the limbs. |