Forty-two patients who had had an arthrodesis for instability of the cervical spine resulting from trauma were followed clinically for a minimum of seven years (median, seventeen years and six months). The ages of the patients at the time of the injury ranged from one year and eleven months to fifteen years and eleven months. On the basis of a new post-traumatic neck score, which includes an assessment of pain, mobility, neurological status, and function, thirty-two patients (76 per cent) had an excellent result, six (14 per cent) had a good result, and four (10 per cent) had a fair result. No patient had a poor result. There was no notable deterioration of the clinical result with an increased duration of follow-up. Current radiographs of the cervical spine in flexion and extension were available for thirty-one (74 per cent) of the forty-two patients. There was no change in stability, deformity, or the fusion mass after healing or with an increased duration of follow-up, but there was a significant increase in osteoarthrotic changes in the unfused segments of the cervical spine after an increased duration of follow-up (p = 0.0001). Complications included spontaneous extension of the fusion mass in sixteen patients (38 per cent), mild pain or dysesthesias at the iliac-crest donor site in six patients (14 per cent), superficial infection at a bone-graft donor site in one patient (2 per cent), an incorrect level of arthrodesis in one patient (2 per cent). One patient had instability secondary to juvenile rheumatoid arthritis, which developed after treatment of the original injury, and she needed a reoperation. We concluded that spinal arthrodesis for fractures and dislocations of the cervical spine in children and adolescents can be accomplished safely, with an acceptable clinical outcome, a low rate of complications, and minimum morbidity after long-term follow-up. Pain, neurological status, and function do not change markedly, but mobility may decrease with an increased duration of follow-up. Our patients had a decrease in mobility, associated with an increase in osteoarthrotic changes, as seen on radiographs (p = 0.05).