Spinal cord injury remains a common complication of trauma. In an average year, 10,000 people will sustain permanent neurologic damage from traumatic cord injury.1 The cost to society, including acute and chronic care, averages $1 billion annually.2 Automobile accidents remain the most common overall cause of spinal trauma, although diving accidents retain the highest per case injury rate.3 Although there has been little advance in the treatment of cord injuries, prehospital care is vital to patient care by early recognition, treatment, and prevention of further injury.
The human spine consists of 33 vertebrae of which 26 are separated by flexible intervertebral discs. Viewing from anterior to posterior, the entire spinal complex is formed by: Anterior longitudinal ligament (ALL), vertebral body, posterior longitudinal ligament (PLL), spinal canal, laminae, ligamenta flava, capsular ligaments, and nuchal ligament complex (interspinous, supraspinous, and infraspinous ligaments). An injury is considered unstable if both the anterior column (ALL, vertebral body, and PLL) and posterior column are traumatically disrupted at one level. This, however, is not an important prehospital consideration since EVERY suspected cord injury should be treated as unstable until proven otherwise.
Injuries to the cord itself occur in approximately 15% of vertebral injuries and may occur even in the absence of radiographically demonstrable trauma.4 Cord injury may occur primarily through three mechanisms. First, transection of neurons occurs secondary to penetrating or massive blunt trauma with disruption of the vertebral column. Second, elderly patients with cervical osteoarthritis and spondylosis may develop compression of the spinal cord after forced cervical spine extension.5 Vascular damage to the cord, including extradural and epidural hematomas, is the final mechanism of traumatic neural injury.
The maximum neurologic deficit following blunt spinal trauma is often not seen immediately but seems to progress and extend over many hours. Injury, initiated by free-radical-induced peroxidation, results in a substantial decrease in cord blood flow. Hemorrhagic necrosis of gray and white matter is the resulting effect.6
Suspicion, not necessarily recognition, of spinal cord injuries is a key responsibility of pre-hospital personnel. A spinal injury should be suspected in trauma victims with 1) impaired consciousness with craniofacial trauma, 2) complaints of neck or back pain, 3) evidence of significant head or facial trauma, 4) signs of focal neurologic deficit, 5) unexplained hypotension, or 6) suggestive mechanism of injury associated with other distracting painful injuries.
Recognition of cord injury is vitally important if prehospital personnel, such as air medical transport teams, have the capability to initiate treatment in the field. A basic neurologic exam includes testing of strength, sensation, reflexes, and observation of breathing pattern. It is important to document any incomplete cord lesion, since these will often require decompression surgery and carry a much better prognosis than complete transections. The three most common incomplete cord lesions include the 1)central cord syndrome - greater deficit in upper extremities than in lower extremities, 2) Brown-Sequard syndrome - ipsilateral motor paralysis with contralateral sensory hypesthesia, and 3) anterior cord syndrome - paralysis and hypalgesia with preservation of position, touch, and vibratory sensations.
Prehospital treatment of suspected spinal cord trauma consists of effective immobilization and , if applicable, pharmocologic treatment. As in all trauma, the airway, breathing, and circulation evaluation takes precedence. Next, the head and trunk are stabilized by holding the head firmly in a straight ahead position with two hands. The second care provider should then place a firm extrication collar around the neck. The patient should then be transferred to a spine board using log roll precautions. If the patient is found in a sitting position, the short spine board is used to splint the cervical and thoracic spine followed by transfer to a long spine board.7
Pharmocologic treatment of spinal injuries consists of a bolus and 23 hour maintenance dose of steroids. A randomized controlled study published in the New England Journal of Medicine in 1990 concluded that methylprednisolone improves neurologic recovery when given in the first 8 hours following injury. The dose that was used in the study was a 30 mg/kg bolus followed by a 5.4 mg/kg infusion for 23 hours. An improvement of one spinal cord level occurred in both complete and incomplete cord injuries.8
In summary, spinal cord injury remains a devastating, life-changing problem. EMA has a vital role in evaluation, diagnosis, and prevention of further spinal cord injury. Until a definitive cure can be found, steroids remain as the only treatment against the potential permanent disability of this disease.
1 Traften PD: Spinal cord injuries, Surg Clin North Am 6(1):61, 1982.
2 Bouzarth WF: Spinal injuries. In Schwartz, G, editor, Principles and Practice of Emergency Medicine, Philadelphia, 1978, WB Saunders Co.
3 Kewalismani LS, Kraus JF: Acute spinal cord lesion from diving, West J Med 126:353, 1877.
4 Riggins RS, Kraus JF: The risk of neurologic damage with fractures of the vertebrae, J Trauma 17:126, 1977.
5 Hardy AG: Cervical spinal cord injury without bony injury, Paraplegia 14:296, 1977.
6 Allen RL, Perot PL, Gudeman SK: Evaluation of acute nonpenetrating cervical spine cord injuries with CT metrizamide myelography. J Neurosurg 63:510, 1985.
7 Heckman, JD: Emergency care and transportation of the sick and injured, Wisconsin, 1987, Banta Company.
8 Bracken MB, et al: A randomized controlled trial of
methylprednisolone or naloxone in the treatment of acute spinal-cord injury.
N Engl J Med 322:20, 1990.