Surgical treatment of adult scoliosis - Is anterior apical release and fusion necessary for the lumbar curve?

Study Design. A retrospective study. Objectives. To analyze radiographic and functional outcomes after posterior segmental spinal instrumentation and fusion (PSSIF) with and without an anterior apical release of the lumbar curve in adult scoliosis patients. Summary of Background Data. No comparison study on PSSIF of adult lumbar scoliosis with apical release versus without has been published. Methods. Forty-eight adult patients with lumbar scoliosis (average age at surgery 49.6 years, average follow-up 3.7 years) who underwent PSSIF were analyzed with respect to radiographic change, perioperative and postoperative complications, and Scoliosis Research Society (SRS) outcome scores. Twenty-three patients underwent an anterior apical release of the lumbar curve via a thoracoabdominal approach followed by PSSIF (Group I). The remaining 25 patients underwent a PSSIF of the lumbar curve followed by anterior column support at the lumbosacral region through an anterior paramedian retroperitoneal or posterior transforaminal approach (Group II). Results. Before surgery, Group I showed a somewhat larger lumbar major Cobb angle (63.2 vs. 55.9, P = 0.07), and both groups demonstrated significant differences in lumbar curve flexibility (26.9% vs. 37.2%, P = 0.02) and thoracolumbar kyphosis (27.0 vs. 15.0, P = 0.03). After surgery, at the ultimate follow-up, there were no significant differences in major Cobb angle, C7 plumbline to the center sacral vertical line (P = 0.17), C7 plumbline to the posterior superior endplate of S1 (P = 0.44), and sagittal Cobb angles at the proximal junction (P = 0.57), T10-L2 (P = 0.24) and T12-S1 (P = 0.51). There were 4 pseudarthroses in Group I and one in Group II (P = 0.02). Postoperative total normalized SRS outcome scores at ultimate follow-up were significantly higher in Group II (69% vs. 79%, P = 0.01). Conclusion. Posterior segmental spinal instrumentation and fusion without anterior apical release of lumbar curves in adult scoliosis demonstrated better total SRS outcome scores and no differences in radiographic parameters without differences in clinical complications. However, the use of BMP in some of these patients (44%) may have also contributed to these differences.