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Cervical spine injuries in infants and children are usually associated with motor-vehicle accidents, falls, diving 129accidents, sports injuries, gunshot injuries, and, occasionally, child abuse. They range broadly from minor softtissue injuries to severe fracture-- dislocations with spinal cord injury or sudden death. Although rare, the injuries are worthy of special attention because of particular aspects relating to the pediatric cervical spine, including unique features of developmental anatomy, injury patterns, treatment, and prognosis. Appropriate algorithms for evaluation and management are essential for the care of these injured children. Deformity, instability, posttraumatic stenosis, and neurologic sequelae may be prevented with early recognition and appropriate management of those at risk.
Developmental Anatomy of the Cervical Spine
In order to adequately understand the differences in injury patterns unique to the pediatric cervical spine, it is essential to understand the anatomic and developmental features that are unique to infants and children.
The notochord is formed by week two of fetal development and is in close proximity to the paraxial mesoderm (mesenchymal tissue running parallel to the notochord), which becomes segmented into four cranial and eight cervical somites at weeks two and three1,2. The somites each differentiate into cranial and caudal halves, which then reunite with the caudal and cranial halves, respectively, of the adjacent somite, forming each provertebra1,2. The notochord eventually constitutes the apical and alar ligaments as well as the nucleus pulposus of each intervertebral disc1,2. During weeks five and six, chondrification takes place in each half of the vertebral body and neural arch1,2. Finally, ossification takes place in each body and lateral mass1-3.
The Atlas
The atlas develops from three ossification centers: the two primary ossification centers of the lateral masses, which are ossified at birth, and one secondary ossification center for the body, which ossifies at approximately one year of age (Fig. 1)4,5 The posterior arches fuse by the age of three or four years; the neurocentral synchondroses between the lateral masses and the body fuse at approximately seven years of age6.
The Axis
The axis is derived from five primary ossification centers, including two lateral masses (or neural arches), an odontoid process (which comprises two condensed longitudinally oriented halves at birth), and a body or centrum (Fig. 1). There are two secondary centers: the ossiculum terminate...