Rigid Instrumentation for Neuromuscular Scoliosis Improves Deformity Correction Without Increasing Complications.

STUDY DESIGN Retrospective chart and radiographic review. OBJECTIVE To evaluate spinopelvic fixation technical advancements for the treatment of neuromuscular scoliosis. SUMMARY OF BACKGROUND DATA Implants for vertebral and pelvic fixation have evolved without data demonstrating the benefit for neuromuscular scoliosis. The aim of this study was to evaluate this evolution in terms of deformity correction, complications, and implant cost. METHODS Patients treated with posterior spinal fusion to the pelvis for neuromuscular scoliosis with minimum 1-year follow-up from 1998 to 2012 were reviewed. Constructs were defined as nonrigid (>50% sublaminar wire fixation with Galveston or iliac screw pelvic fixation) and rigid (≥50% pedicle screw fixation with iliac or sacral alar iliac screw pelvic fixation). RESULTS Eighty patients were identified: cerebral palsy (55%), myelomeningocele (16%), syndrome (8%), muscular dystrophy (15%), or other neuromuscular disorders (6%). A total of 95% were nonambulatory. Mean follow-up was 3.9 years (range 1-12 years). Construct types were 23 nonrigid and 57 rigid. Estimated construct cost was greater in the rigid group at $15,488 as compared with $3128 in the nonrigid group despite the lower anchor density in the rigid construct group (1.38 vs. 1.80, P < 0.001). Open anterior releases were more frequently performed in the nonrigid group (13/23 vs. 5/57, P < 0.001). Deformity correction at final follow-up was significantly greater for both Cobb angle and pelvic obliquity in the rigid group. The rates of wound infection, wound dehiscence, implant prominence, and mechanical failure of the fixation were not significantly different. The pseudarthrosis rate requiring revision surgery was 22% in nonrigid group and 5% in the rigid group (P = 0.026). CONCLUSION Advances in spinopelvic fixation have resulted in improved deformity correction with lower rates of pseudarthrosis and a decreased need for anterior release. This study demonstrates the benefits of modern spinopelvic fixation techniques.