Factors influencing the result of posterior spinal fusion in the treatment of adolescent idiopathic scoliosis.

Sixty-six consecutive patients with adolescent idiopathic scoliosis treated by posterior spinal fusion using Harrington distraction compression instrumentation were followed for a minimum of 3 years. Initial surgical correction was satisfactory, but during the follow-up period, mean 4.4 years (3-5 years), there was a loss of correction. Several factors (age, sex, the number of vertebrae in the fusions, and the use of cross wires) were important influences on correction. A method of assessing the balance of a posterior spinal fusion is described that is useful when assessing radiographs.