Spinal cord injury
Spinal cord injury is damage to the spinal cord that causes loss of sensationand motor control. Approximately 10,000 new spinal cord injuries (SCIs) occur each year in the United States. About 250,000 people are currently affected. Spinal cord injuries can happen to anyone at any time of life. The typicalpatient, however, is a man between the ages of 19 and 26, injured in a motorvehicle accident (about 50% of all SCIs), a fall (20%), an act of violence (15%), or a sporting accident (14%). Alcohol or other drug abuse plays an important role in a large percentage of all spinal cord injuries. Six percent of people who receive injuries to the lower spine die within a year, and 40% of people who receive the more frequent higher injuries die within a year.
Short-term costs for hospitalization, equipment, and home modifications are approximately $140,000 for an SCI patient capable of independent living. Lifetime costs may exceed one million dollars. Costs may be 3-4 times higher for the SCI patient who needs long-term institutional care. Overall costs to the American economy in direct payments and lost productivity are more than $10 billion per year.
The extent to which movement and sensation are damaged following spinal cordinjury depends on the level of the injury, since nerves leaving the spinal cord at different levels control movement and sensation in diffferent parts ofthe body.
Damage below the base of the rib cage causes paralysis and loss of sensationin the legs and trunk below the injury. Injury at this level usually does nodamage to the arms and hands. Paralysis of the legs is called paraplegia. Damage above this level involves the arms as well as the legs. Paralysis of allfour limbs is called quadriplegia or tetraplegia. Cervical or neck injuries not only cause quadriplegia but also may cause difficulty in breathing. Damagein the lower part of the neck may leave enough diaphragm control to allow unassisted breathing. Patients with damage just below the base of the skull, require mechanical assistance to breathe.
Symptoms also depend on the extent of spinal cord injury. A completely severed cord causes paralysis and loss of sensation below the wound. If the cord isonly partially severed, some function will remain below the injury. Damage limited to the front portion of the cord causes paralysis and loss of sensations of pain and temperature. Other sensation may be preserved. Damage to the center of the cord may spare the legs but paralyze the arms. Damage to the right or left half causes loss of position sense, paralysis on the side of the injury, and loss of pain and temperature sensation on the opposite side.
Complications of spinal cord injury may include:
- deep venous thrombosis, or blood clotting
- pressure ulcers of the skin
- spasticity and contracture of unused muscles
- heterotopic ossification, or growthof bony tissue within muscle and tendons
- autonomic dysreflexia, a lack of regulation of certain body systems
- loss of bladder and bowel control
- sexual dysfunction
A person who may have a spinal cord injury should not be moved. Treatment ofSCI begins with immobilization. This strategy prevents partial injuries of the cord from severing it completely. Use of splints to completely immobilize suspected SCI at the scene of the injury has helped reduce the severity of spinal cord injuries in the last two decades. Intravenous methylprednisone, a steroidal anti-inflammatory drug, is given during the first 24 hours to reduceinflammation and tissue destruction.
Rehabilitation after spinal cord injury seeks to prevent complications, promote recovery, and make the most of remaining function. Rehabilitation is a complex and long-term process. It requires a team of professionals, including aneurologist, physiatrist or rehabilitation specialist, physical therapist, and occupational therapist. Other specialists who may be needed include a respiratory therapist, vocational rehabilitation counselor, social worker, speech-language pathologist, nutritionist, special education teacher, recreation therapist, and clinical psychologist. Support groups provide a critical source of information, advice, and support for SCI patients.
Some limited mobility and sensation may be recovered, but the extent and speed of this recovery cannot be predicted. Experimental electrical stimulation has been shown to allow some control of muscle contraction in paraplegia. Thisexperimental technique offers the possibility of unaided walking. Further development of current control systems will be needed before useful movement ispossible outside the laboratory.
The physical therapist focuses on mobility, to maintain range of motion of affected limbs and reduce contracture and deformity. Physical therapy helps compensate for lost skills by using those muscles that are still functional. Italso helps to increase any residual strength and control in affected muscles.A physical therapist suggests adaptive equipment such as braces, canes, or wheelchairs.
An occupational therapist works to restore ability to perform the activitiesof daily living, such as eating and grooming, with tools and new techniques.The occupational therapist also designs modifications of the home and workplace to match the individual impairment.
A pulmonologist or respiratory therapist promotes airway hygiene through instruction in assisted coughing techniques and postural drainage. The respiratory professional also prescribes and provides instruction in the use of ventilators, facial or nasal masks, and tracheostomy equipment where necessary.
Pressure ulcers are prevented by turning in bed at least every two hours. Thepatient should be turned more frequently when redness begins to develop in sensitive areas. Special mattresses and chair cushions can distribute weight more evenly to reduce pressure. Electrical stimulation is sometimes used to promote muscle movement to prevent pressure ulcers.
Range of motion (ROM) exercises help to prevent contracture. Chemicals can beused to prevent contractures from becoming fixed when ROM exercise is inadequate. Phenol or alcohol can be injected onto the nerve or botulinum toxin directly into the muscle. Botulinum toxin is associated with fewer complications, but it is more expensive than phenol and alcohol. Contractures can be released by cutting the shortened tendon or transferring it surgically to a different site on the bone where its pull will not cause as much deformity. Such tendon transfers may also be used to increase strength in partially functionalextremities.
Normal bowel function is promoted through adequate fluid intake and a diet rich in fiber. Evacuation is stimulated by deliberately increasing the abdominal pressure, either voluntarily or by using an abdominal binder.
Bladder care involves continual or intermittent catheterization. The full bladder may be detected by feeling its bulge against the abdominal wall. Urinarytract infection is a significant complication of catheterization and requires frequent monitoring.
Counseling can help in adjusting to changes in sexual function after spinal cord injury. Erection may be enhanced through the same means used to treat erectile dysfunction in the general population.
The prognosis of SCI depends on the location and extent of injury. Injuries of the neck above C4 with significant involvement of the diaphragm hold the gravest prognosis. Respiratory infection is one of the leading causes of deathin long-term SCI. Overall, 85% of SCI patients who survive the first 24 hoursare alive 10 years after their injuries. Recovery of function is impossibleto predict. Partial recovery is more likely after an incomplete wound than after the spinal cord has been completely severed.