Is it time to stop immobilizing kids?
Growing evidence appears to support modified spinal immobilization protocols for pediatric trauma patients
Rescue 14 arrives at the scene of a motor vehicle crash. A small sedan was T-boned on the driver's side by another car; there is about 4 inches of intrusion into the passenger space. The driver, a 30-year-old female appears to have struck her head against her door's window and is complaining of lateral neck and left parietal head tenderness. Her 4-year-old daughter, restrained in a car seat in the passenger side rear seat, is crying and trying to reach her mother. There are no obvious signs of external injury to the child.
Should the child's spine be immobilized as a precaution?
Over the past decade, there has been a shift in the out-of-hospital practice of cervical spine immobilization for patients who have experienced a mechanism of injury with no neurological deficits. Studies have shown that the rate of spinal cord injury (SCI) is very low in the trauma patient and the vast majority patients with a SCI complain of some form of neurologic deficit. In addition, it has become apparent that the traditional use of rigid collars and a hard spine board has the potential to cause pain, injuries and compromise airway patency.
As a result an increasing number of EMS systems have implemented modified spinal restriction protocols that utilize a range of techniques and equipment to protect the cervical spine, depending upon the patient's presentation. These range from no restrictions at all, to the use of soft collars and patient self extrication from motor vehicle collisions.
Yet many of these modifications do not currently exist for pediatric patients. Given the anatomic, physiologic and psychological differences between children and adults, many of the original studies caution against the extrapolation of their findings to the pediatric population. However, research is beginning to emerge that argues for extending the same modification of immobilization criteria for adult patients to children who present similarly.
The body of a child or infant differs from an adult in many ways. Specific to the spinal column, the vertebral bones of the newborn are very soft, consisting more of cartilage than bone, and not yet fully formed in shape and hardness. In addition, the muscles and ligaments that wrap around the vertebrae are not yet fully developed. As a result, the spinal column is more flexible and more capable of rotational, twisting motion.
As the infant grows, the vertebrae continue to grow, harden and take their final shapes. The ligaments and muscles strengthen as well. The spine lengthens, becomes less flexible and becomes strong enough to carry the weight of the torso and head as the infant begins to sit, stand and eventually walk. The familiar "double S" shape of the spine takes form as the young child becomes increasingly active. Full formation of the spine usually occurs between the ages of 7 and 9 years, although incremental changes continue to occur through adolescence until the early twenties.
Spinal injury patterns
The developing anatomy of the pediatric spine is directly related to the injury pattern seen in young trauma patients. An infant's head is disproportionally larger and heavier to the rest of the body as compared to an adult; this means that infant and young children tend to "lead with the head" when falling forward. Coupled with the weak, incomplete formation of the cervical vertebrae there is a significant incidence of injuries to the C1 through C4 vertebrae in children under 2 years of age. As the child ages and the vertebrae begin to resemble an adult's, the injuries shift toward the lower cervical vertebrae, C5 through C7.
Pediatric patients also experience a greater incidence of vertebral dislocations and subluxations as compared to adults, as well as soft tissue injuries to the ligaments and muscles. In addition, children also experience a greater proportion of spinal cord injuries without radiographic abnormality (SCIWORA), where there appears to be no damage to the spinal column upon X-ray or computed tomography (CT), but the children are neurologically symptomatic with abnormal findings found during magnetic resonance imaging (MRI).
The incidence of spinal cord injuries is very low in children and occurs after some type of blunt force mechanism of injury such as a motor vehicle crash, fall, or violent shaking. SCI rates of 1-2 percent in pediatric patients experiencing blunt trauma have been reported.[1, 2]
It appears that children with spinal cord injuries present with signs and symptoms similar to adults. Abnormal neurological findings, torticollis (where the head is persistently turned to one side due to very painful neck muscle spasms), pain and tenderness to the spine upon palpation were evident. In one study, the occurrence of a spinal cord injury after a blunt force mechanism of injury was correlated to decreased Glasgow Coma Scale (GCS) score, head injury and chest trauma.
Dangers of radiation for children?
It's not absolutely clear whether there is a risk of cancer from radiation exposure as a result of diagnostic testing, such as X-rays or CT scans. Children grow at a rapid pace, with cells dividing at a much higher rate than adults. There is a theoretically a greater chance of malignancy such as thyroid or breast cancer developing in children after repeated radiation exposures, although the information is limited at best.
It is not clear whether there is a "safe" level of radiation from diagnostic testing. Nevertheless, agencies such as the Environmental Protection Agency (EPA), and the National Toxicology Program classify x- and gamma radiation as known human carcinogens and set recommended limits of exposure.
Is it possible to "clear" the pediatric c-spine?
Given the concern of exposing children to unnecessary diagnostic radiation, researchers have looked at whether the risk of a spinal injury could be assessed clinically, without routine use of X-rays or CT scans. Large scale studies in the U.S. and Canada demonstrated that medical providers that followed a set of clinical protocols could safely release an adult patient from spinal motion restrictions without using radiographic imaging.[7, 8] The National Emergency X-Radiography Utilization Study (NEXUS) criteria for ruling out spinal injury secondary to a blunt force mechanism of injury include:
- no tenderness at the posterior midline of the cervical spine;
- no focal neurologic deficit;
- no altered level of alertness;
- no evidence of intoxication;
- no clinically apparent, painful, distracting injury
Several studies have looked at the possibility of applying clinical protocols to rule out cervical spine injuries in pediatric patients. One prospective study collected both clinical and radiologic information about pediatric trauma patients who required evaluation of the cervical spine. The researchers concluded that it was possible to safely clear the possibility of injury without radiologic testing.
In one study of 233 patients under the age of 15, researchers looked at the utilization of CT scans before and after the implementation of a NEXUS-based clinical protocol. They determined that there was a significant decrease in utilization after the protocol was implemented.
A more recent retrospective study that looked at children 5 years or younger revealed that all of the patients who had confirmed cervical spine injuries had clinical findings (abnormal neurological exam, torticollis and pain long the midline of the spine. The researchers concluded that it could be safe to clear the pediatric c-spine without radiographic diagnostics, even in very young patients.
Concerns about the differences in c-spine anatomy and development of pediatric patients as compared to adults have kept the management of potential injury fairly conservative. With the recent investigations in this area, it may be time for emergency care practitioners to reconsider the practice of spinal immobilization for children and develop clinically appropriate guidelines to reduce the practice to those who are at risk for spinal injuries.
- Dietrich AM, Ginn-Pease ME, Bartkowski HM, King DR. Pediatric cervical spine fractures: predominantly subtle presentation. J Pediatr Surg. 1991;26(8):995.
- Patel JC, Tepas JJ 3rd, Mollitt DL, Pieper P. Pediatric cervical spine injuries: defining the disease. J Pediatr Surg. 2001;36(2):373.
- Hale DF, Fitzpatrick CM, Doski JJ, Stewart RM, Mueller DL. Absence of clinical findings reliably excludes unstable cervical spine injuries in children 5 years or younger. J Trauma Acute Care Surg. 2015 May;78(5):943-8.
- Martin BW, Dykes E, Lecky FE. Patterns and risks in spinal trauma. Arch Dis Child 2004;89:860–865. http://adc.bmj.com/content/89/9/860.full.pdf Retrieved 23 July 2015.
- Kleinerman, R. A. (2006). Cancer risks following diagnostic and therapeutic radiation exposure in children. Pediatric Radiology, 36(Suppl 2), 121–125. doi:10.1007/s00247-006-0191-5
- American Cancer Society. Do x-rays and gamma rays cause cancer? Retrieved 25 July 2015.
- Hoffman JR et al (NEXUS Study Group). Validity of a Set of Clinical Criteria to Rule Out Injury to the Cervical Spine in Patients with Blunt Trauma. N Engl J Med 2000; 343:94-99.
- Stiell IG, Wells GA, Vandemheen KL, et al. The Canadian C-spine rule for radiography in alert and stable trauma patients. JAMA 2001;286:1841–8.
- Anderson RC et al. Utility of a cervical spine clearance protocol after trauma in children between 0 and 3 years of age. J Neurosurg Pediatr. 2010 Mar;5(3):292-6.
- Rosati SF et al. Implementation of pediatric cervical spine clearance guidelines at a combined trauma center. J Trauma Acute Care Surg. 2015 Jun;78(6):1117-21.