Spinal Cord Injury (Paraplegia, Quadriplegia)

– An insult to the spinal cord that results in alteration of autonomic, motor, and sensory function below the level of injury. Paraplegia involves the lower extremities; quadriplegia involves all extremities. Injury to the cord may result in incomplete or total transection.

Causes and Incidence

Spinal cord injury (SCI) may be caused by external trauma or internal disease or degeneration. Common traumatic causes of spinal cord injury include vehicle accidents (48%), falls (21%), acts of violence (15%), and sports injuries (14%). Metastatic carcinoma, spinal cord tumors, spondylosis, and vertebral disk degeneration are common nontraumatic causes of spinal cord injury. The worldwide incidence of SCI is about 55 million a year, and about 35 million people survive the acute injury. The worldwide number of SCI survivors is estimated to be 500 million to 900 million. About 10,000 cases occur in the United States annually, and at least 100,000 individuals are living with SCI in the United States today. About 55% of individuals are quadriplegic, and the remaining 45% are paraplegic. Traumatic injury occurs most often in young adult men, and nontraumatic injury is more common in individuals over 50 years of age.

Disease Process

Injury may be direct or indirect. Direct injuries involve compression or transection of the cord by the causal agent (e.g., bone fragments, bullets, or other external debris in the cord; external severing of the cord; tumor growth on the cord, or bony overgrowth of the spine that squeezes the cord). Tissue necroses around the site of injury. Indirect injury involves compression, overstretching, rotation, wedging, or misalignment of the cord, which results in edema, swelling, and localized hemorrhage. This in turn reduces vascular perfusion, decreases oxygen tension, and increases the norepinephrine concentration, producing ischemia and tissue necrosis. Necrosed tissue is removed by bodily functions within a month of injury and is gradually replaced by connective scar tissue and glial fibers.

Symptoms

Manifestations differ by level and completeness of injury.

Initial phase (spinal shock)
Partial or complete flaccid paralysis below injury level; partial or complete loss of proprioception, pain, touch, pressure, temperature, spinal reflexes, vasomotor tone, and visceral and somatic sensation below injury level; loss of ability to perspire below injury level; dysfunction of bowel and bladder; impaired or absent respiration if injury is above C5; bradycardia; hypotension

Autonomic hyperreflexia
Onset occurs after resolution of spinal shock and return of reflex activity; affects mostly those with an injury at T6 or above; paroxysmal hypertension, bradycardia, pounding headache, profuse sweating and flushing above injury level, nausea, nasal stuffiness

Long-term
Muscle spasms; exaggerated deep tendon reflexes; contractures; hyperesthesia immediately above injury level; paresthesias; neuropathic pain; impotence; trophic ulcers; dry skin; nail changes; skin breakdown

Potential Complications

The immediate complications are generally life threatening and include respiratory failure, hemorrhage, and cardiac failure. Long-term complications include pneumonia and atelectasis, cardiovascular disease, orthostatic hypotension, severe bradycardia, hyperkalemia, deep vein thrombosis, pulmonary embolism, gastric atony, ileus, bladder and kidney infections, decubiti, pathologic fractures, heterotrophic ossification, degeneration of upper extremity joints, emotional debility, and suicide.

Diagnostic Tests

Clinical evaluation
Absence of reflexes, flaccidity, loss of sensation below injury level; examination of dermatomes and muscles to determine level of injury

Spinal xrays
Vertebral fractures, bony overgrowth

Computed tomography/ magnetic resonance imaging
Evidence of cord compression and edema or tumor formation

Lumbar puncture/ myelography
Spinal blockage

Treatments

Surgery
Initial: laminectomy or fusion for decompression and stabilization; wound debridement; placement of cervical tongs or halo traction for stabilization; tracheotomy for mechanical ventilation if needed Long term: myotomies, tenotomies, rhizotomies, and muscle transplantation to treat spasticity; contracture release; debridement of decubiti; spinal instrumentation to halt scoliosis; penile implant for impotence; colostomy for atonic colon; urinary diversion for incontinence or retention.

Drugs
Initial: massive corticosteroid therapy to improve outcome; prophylactic antiinfective drugs for open wounds; analgesics for pain; anticoagulants to prevent emboli and thrombus formation; antihypertensives for hyperreflexia; antianxiety agents to reduce emotional stress Long term: muscle relaxants for spasms; stool softeners and laxatives for constipation; anticholinergics for bladder spasticity.

General
Initial: spinal stabilization with backboard or cervical collar on initial transport; mechanical ventilation if necessary; cardiac monitoring; blood gases; monitoring of intake and output; vital signs and neurologic vital signs; maintenance of skeletal traction and body alignment; repositioning, turning every 2 hours; passive range-of-motion exercises; footboard; all activities of daily living (ADLs) performed for person; monitoring of bowel and bladder function; monitoring of skin integrity Long term: bowel training using digital stimulation, gravity, high-fiber diet, regularity, adequate hydration; bladder training using intermittent catheterization; physical therapy to diminish orthostatic hypotension, increase strength and endurance, decrease muscle spasticity, prevent contractures, teach functional mobility skills (e.g., transfer techniques, wheelchair manipulation); occupational therapy to aid adaptation of ADLs (e.g., feeding, bathing, hygiene, grooming, dressing) and to teach use of adaptive equipment; respiratory therapy to increase vital capacity and tidal volume; recreational therapy to enhance quality of life; speech therapy if injury is high enough to affect swallowing or when permanent ventilation requires alternative communication systems; long-term medical follow-up by physical medicine, urology, gastroenterology, and respiratory specialists to reduce complications; vocational training; counseling of individual and family for support and adaptation; instruction in bowel and bladder programs, skin inspection, pressure relief, decubitus prevention, prevention or early treatment of urinary tract and upper respiratory infections, and recognition of hyperreflexia.