Prospective comparison of gait and trunk range of motion in adolescents with idiopathic thoracic scoliosis undergoing anterior or posterior spinal fusion

Study Design. Prospective evaluation of gait and spinal range of motion (ROM) in adolescent idiopathic scoliosis (AIS) patients undergoing either an anterior or a posterior spinal fusion. Objective. Compare changes in gait and spine ROM between AIS patients undergoing either an anterior or posterior spinal fusion. Summary and Background Data. Problems with AIS posterior spinal fusion and attempts to minimize the number of spinal segments fused have led to the promotion of anterior spinal fusion. Comparison of functional outcomes of the two surgeries has not been reported. Materials and Methods. Thirty-one patients with single or double thoracic AIS undergoing an anterior (n = 16) or posterior (n = 15) instrumented spinal fusion underwent gait and triplanar ROM tests before surgery and 24 months postoperative. Videography with reflective surface markers on the scapula, spine, and pelvis were used to quantify changes in gait and trunk ROM. Results. Surgical results indicated that an average of four fewer levels was fused and the lowest instrumented vertebrae were one level higher in the spine for the anterior group compared to the posterior group. Gait results showed no change in gait speed and no change in coronal and sagittal plane kinematics, regardless of group. Transverse plane motion during gait was reduced in both groups. Spinal ROM results indicated motion loss in all three planes, regardless of group, with the posterior group having less postoperative ROM than the anterior group. Unlinking surgical approach from number of fused levels and lowest instrumented vertebrae with a subset of subjects also indicated less postoperative ROM for the posterior group. Conclusions. The surgical and ROM results seem to favor the anterior approach over the posterior approach for the classification of patients in this investigation. However, it should be noted that both groups had decreased postoperative ROM.