Traumatic subluxation of the axis after hyperflexion injury of the cervical spine in children

Six cases of children (four boys and two girls, mean age 11 years) who had traumatic subluxation of the axis (C2) were reviewed retrospectively. Initial radiographs demonstrated no detectable vertebral fracture in any of the children. However, a slight anterior subluxation of C2 was observed in three of the patients. Radiographs, taken at 1 month after injury in all but one patient, revealed a progression of the subluxation and a local kyphosis in all of the patients. Four of the children were treated conservatively with a cervical brace, and an improvement of both the kyphosis and the anterior slippage of C2 was obtained accompanied by an anteroposterior growth of the C3 vertebral body. The kyphosis of two of the patients became severe and, ultimately, these patients underwent fusion surgery. At the follow-up, none of the patients presented with any significant symptom. For the correct diagnosis of traumatic subluxation of C2, sequential radiographs to confirm the progression of subluxation and local kyphosis are mandatory. Conservative treatment rather than early surgical treatment may be chosen for this injury, because mild and moderate kyphosis can be corrected spontaneously by remodeling of the cervical spine.