Distal fusion level, complications, and reoperations in individuals with cerebral palsy undergoing surgery for scoliosis

Purpose To compare radiological outcome, complications and reoperations in individuals with cerebral palsy and scoliosis fused to the fifth lumbar vertebra (L5), the sacrum, or the ilia. Methods 208 individuals were identified in the national quality registry Swespine. Lowest level of fusion was L5 in 58, the sacrum in 92, and the ilia in 58 individuals. A subanalysis on 58 matched pairs operated to L5 or the pelvis (sacrum = 42, ilia = 16) with similar pelvic obliquity (± 5°) was performed. Results The median (interquartile range) follow-up for the last radiograph was 1.7 (1.7) years and for reoperations 6.0 (5.9) years. Preoperatively, median Cobb angle of the major curve was 65° (23°) in the L5 group, 68° (28°) in the sacrum group, and 78° (25°) in the ilia group (p = 0.006). Preoperative median pelvic obliquity according to Maloney was 16° (19°), 21° (13°), and 27° (28°), respectively (p = 0.004). Immediate postoperative Cobb angles were 28° (18°), 28° (16°), and 32° (25°), respectively (p = 0.11). Immediate postoperative pelvic obliquity was 7° (10°), 7° (8°), and 8° (10°), respectively (p = 0.28). The median change in pelvic obliquity from the first to the last postoperative radiograph was − 5° (7°), − 3° (6°), − 3° (6°), respectively (p = 0.55). 7 (12%), 11 (12%), and 7 (12%) patients required at least one reoperation (p = 1.0), respectively. In the matched analysis, no significant differences in the radiological outcomes were found (all p ≥ 0.38). Conclusions Maintained curve and pelvic obliquity correction with no significant difference in complication and reoperation rates were found irrespective of distal fusion level.