Efficacy and Risk Factors, for Complications Associated with Growing Rods, in the Management of Progressive Early-Onset Scoliosis

Abstract

Introduction Growing-rod spinal instrumentation systems are a valuable option for managing progressive early-onset scoliosis. However, some studies had suggested that its efficacy may be lost over a period time and could be counterbalanced by a high rate of complications. The objective of this study was to determine the efficacy and safety of growing rods for the treatment of progressive early-onset scoliosis. Materials and Methods An Institutional Review Board approved cross-sectional study was performed, including patients with early-onset scoliosis treated with growing rods between 1997 and 2012. A retrospective review of the chart and radiographic data were performed. Risk factors for complications were explored using univariate and multivariate analyses. Results Records of 35 patients were included. The mean age at implantation of the rods was 5.8 ± 2.3 years. Overall, 18 patients had a diagnosis of idiopathic scoliosis, 11 with congenital scoliosis, and 6 with neuromuscular scoliosis. The mean Cobb measurement for the preoperative major curves was 66.7 ± 14.4 (range, 42–98) degrees. After a mean of 4 ± 1.4 lengthening procedures, there was a statistically significant improvement in the coronal plane deformity to a mean of 34.9 ± 11.2 degrees ( p < 0.001), resulting in an average decrease of 31.8 ± 14.6 degrees. Following complications have occurred in 11 patients (31.4%): implant failure/fracture (22.9%), surgical site infection (5.7%), and transient brachial plexus injury (2.8%). The only risk factor associated with the presentation of postoperative complications was the total number of lengthening procedures (OR = 2.79). Conclusion Growing rods are effective for reduction of the magnitude of the spinal deformities in patients with progressive early-onset scoliosis before the definite fusion. However, this treatment is related with a relatively high rate of postoperative complications. Those complications appear to be associated with the total number of lengthening procedures previous to the definitive fusion. Therefore, it is advisable to reduce the frequency of lengthening as much as needed for maintaining the correction and allow the longitudinal growing of the spine.