Radiographic and patient-based outcome analysis of different bone-grafting techniques in the surgical treatment of idiopathic scoliosis with a minimum 4-year follow-up: allograft versus autograft/allograft combination.

Background Context: Autograft and allograft have been equally successful in achieving arthrodesis, but whether there is any difference in their effect on patient outcome, especially early, has not been determined.

Purpose: To determine if autograft in addition to allograft is associated with decreased healing period pain, increased early function, or both.

Study Design: This is a retrospective comparative case series.

Patient Sample: A sample of 47 patients, 20 years or younger with adolescent idiopathic scoliosis treated by the same surgeon at the same institution using third-generation segmental spinal instrumentation and arthrodesis.

Outcome Measure: Function and pain were quantified at periodic intervals using the Scoliosis Research Society (SRS) health-related quality of life (HRQoL) questionnaire. Clinical and radiographic follow-ups were completed.

Methods: Freeze-dried corticocancellous allograft (AL) was used in 26 patients and allograft plus iliac crest autograft (AL-AU) in 21 patients. Radiographs and outcome measures, including SRS-24 or SRS-22 HRQoL questionnaires, were obtained preoperatively and at intervals with a 4-year follow-up available for 92% (25/26) of AL patients and 90% (19/21) of AL-AU patients.

Results: There were no differences between the AL and AL-AU groups' ages, curve patterns, and complications. Neither group had a major complication or pseudoarthrosis. There were no main curve size differences at any interval. Pain scores were similar at all intervals: AL/AL-AU preoperative, 4.1/4.0; early follow-up (<1 year), 3.7/4.1; midterm follow-up (1-2 years), 4.4/4.6; and late follow-up (>3 years), 4.1/4.0. Function scores were also similar at all intervals: AL/AL-AU preoperative, 4.7/4.6; early follow-up, 4.2/4.3; midterm follow-up, 4.9/4.9; and late follow-up, 4.5/4.4.

Conclusions: The addition of autograft to allograft did not result in decreased pain or increased function at any time interval up to 4 years. We conclude that the addition of iliac crest autograft does not result in any advantage over freeze-dried allograft alone in the treatment of adolescent idiopathic scoliosis.