Complications in Spinal Fusion for Adolescent Idiopathic Scoliosis in the New Millennium: A Report of the Scoliosis Research Society Morbidity and Mortality Committee

Introduction: Surgical approaches to the management of adolescent idiopathic scoliosis (AIS) have a measurable impact on efficacy of correction, levels fused, and operative morbidity. There is a lack of consensus on the choice of surgical approach for the management of spinal deformity, and the observed variability may be perpetuated by the absence of an evidence-based approach to the surgical management of specific deformities. Recorded complications are an important consideration in choosing a surgical approach to AIS, and an analysis of complications recorded by SRS members may help to guide future decision-making for deformity correction. The purpose of this study is to analyze the recorded complications of anterior, posterior, and combined surgical approaches for the management of AIS as reported by the SRS membership over the past three years; testing the null hypothesis that the surgical approach used for instrumentation and fusion of AIS (anterior-only, posterior, and combined) has no effect on the overall rates, types or frequencies of recorded complications.

Materials and Methods: Of the 58,197 surgical cases submitted by members of the SRS in the years 2001 through 2003; 14,554 (25.0% of the total) were performed for the treatment of scoliosis. The 6,334 patients (10.9% of the total) identified as having had anterior, posterior or combined spinal fusion with instrumentation for the diagnosis of AIS comprised the cohort under study. All reported complications were tabulated and totaled for each of the three types of procedures and statistical analysis conducted.

Results: Complications were reported in 363 (5.7%) of the 6,334 patients in this series. Sixty (5.2%) of the 1,164 patients who underwent anterior fusion and instrumentation experienced complications, 221 (5.1%) of the 4,369 patients who underwent posterior instrumentation and fusion experienced complications and 82 (10.2%) of the 801 patients who underwent combined instrumentation and fusion experienced complications. There was no statistical difference in overall complication rates between anterior and posterior procedures (p = 0.88). The difference in complication rates between anterior or posterior procedures compared to combined procedures, however, was highly significant (p <0 .0001). The most common complications for anterior procedures were pulmonary (excluding embolus) (1.6%). posterior wound infections (1.4%). combined at 3.5%. Neurologic complication rates anterior, and 0.26%, 0.32% 1.75% respectively.

Conclusions: This study demonstrates that complication rates are similar for anterior vs. posterior approaches to AIS deformity correction, however with different distributions of types. Combined anterior and posterior instrumentation and fusion has a significantly higher rate of complications than anterior or posterior instrumentation and fusion alone. The most common complications for anterior and combined procedures were pulmonary whereas the most common complications for posterior procedures were wound infections. The data in this study can be used to counsel patients and their parents with regards to the nature and rates of complications associated with the surgical approaches used in spinal fusion and instrumentation for AIS in the hands of experienced scoliosis surgeons and may help to guide future decision-making for deformity correction in AIS.