Is Routine Postoperative Radiologic Follow-up Justified in Adolescent Idiopathic Scoliosis?

Abstract

Study design: Retrospective review.

Objectives: To determine whether routine periodic radiographic examination is worthwhile in adolescent idiopathic scoliosis (AIS) patients undergoing instrumented fusion with third-generation implants.

Summary of background data: In common practice, patients who have undergone surgery for idiopathic scoliosis are followed up for a minimum of 2 years by clinical assessment and routine radiographic study at 3, 6, 12, and 24 months. The radiation related to these examinations is not negligible. To our knowledge, the use of routine radiographic follow-up after posterior spinal fusion for adolescent idiopathic scoliosis has not been evaluated.

Methods: We retrospectively analyzed full-spine X-rays and clinical records from the first 2 postoperative years of 43 patients. We sought any clinical feature (eg, pain, deformity progression, material protrusion) justifying X-ray, and any relevant radiologic finding (eg, loss of correction, instrumentation loosening, junctional kyphosis).

Results: Excluding the immediate postoperative films, 14.8% of X-rays were clinically justified, 8.3% were associated with a relevant finding, and 4.3% led to a therapy change. All patients with clinical deformity progression had a relevant X-ray finding. Pain was associated with a relevant finding in 23.5% of cases (positive predictive value, 0.1); 7.4% of films with no clinical justification showed a relevant finding (negative predictive value, 0.86). Lower Risser sign increased the risk of having a relevant radiographic finding (p < .05).

Conclusions: With the current use of third-generation implants, routine biplanar postoperative X-rays at 3, 6, 12, and 24 months do not seem to be justified in AIS and should be avoided in mature, asymptomatic patients.

Keywords: Adolescent idiopathic scoliosis; Posterior spinal fusion with instrumentation; Radiation; Utility of postoperative radiographs.