Seven children underwent posterior cervical fusion with cadaveric bone graft and wiring for instability secondary to trauma or a congenital anomaly. None of the operations resulted in solid bone union. One patient was found to have a fibrous union which was stable on flexion-extension roentgenograms. In five patients who had a symptomatic pseudarthrosis, a second operative procedure was performed using autogenous iliac-bone graft. Bone union was subsequently observed in the four who were available for follow-up.