A comparison of different methods used to diagnose pseudarthrosis following posterior spinal fusion for scoliosis.

Pseudarthrosis is a recognized complication of posterior spinal fusion for scoliosis, and its early recognition and repair may prevent loss of correction, failure of the instrumentation, or pain. In this study of 200 fusions for scoliosis, we compared the reliability of different methods that are currently used to determine the presence or absence of a pseudarthrosis. Anteroposterior tomography was found to have the highest rate of correlation (96 per cent), as there was only one false-negative study. Other methods of diagnosis--including anteroposterior, lateral, and oblique radiographs and clinical findings such as loss of correction and back pain--were less accurate.