Prospective evaluation of trunk range of motion in adolescents with idiopathic scoliosis undergoing spinal fusion surgery

Study Design. Prospective evaluation of spinal range of motion in patients with adolescent idiopathic scoliosis undergoing a spinal fusion. Objective. Evaluate changes in triplanar spine range of motion following spinal fusion. Summary and Background Data. Preoperative and postoperative radiographs have been the major form of outcome analysis of adolescent idiopathic scoliosis fusions. Although the radiographs document static positions of the skeletal system, they do not document dynamic changes. Methods. Thirty patients with adolescent idiopathic scoliosis undergoing an instrumented spinal fusion underwent triplanar range of motion tests before surgery and at 12 and 24 months after surgery. Videography with reflective surface markers was used to capture the motions. A fused region, unfused regions above and below the fusion, and a global spinal measure were used to assess changes. Results. Results indicated a loss of motion in the coronal and sagittal planes for the fused and unfused spinal regions and a loss of motion in the coronal, sagittal, and transverse planes for the global measurements. Results also indicated preoperative and continued postoperative right and left lateral flexion asymmetries. No significant correlations were found between the total fused levels and changes in range of motion. No significant correlations were found between the lowest instrumented vertebra and changes in range of motion. Conclusions. Whereas range of motion was reduced in the fused regions of the spine, it was also reduced in unfused regions. The lack of compensatory increase in motion at unfused regions contradicts current theory and suggests early postoperative range of motion therapy to facilitate motion in unfused regions.