Long vs. short fusions for adult lumbar degenerative scoliosis: does balance matters?

Purpose Surgery of adult scoliosis was based upon coronal plane radiographical analysis using Cobb angle measurements, but recently it has been demonstrated that sagittal spinopelvic alignment plays a critical role in determining the final outcome. The aim of this paper is to compare the clinical and radiological results of 81 patients affected by adult scoliosis, treated with short or long fusions, and followed for 2-5 year follow-up. Materials and methods 81 patients affected by degenerative lumbar scoliosis managed by posterior-only surgery were retrospectively evaluated. Fifty-seven patients underwent to a short fusion procedure, while 24 had a long fusion. Clinical and radiographic coronal and sagittal spinopelvic parameters were compared between the two groups. Results Coronal Cobb angle was 24 degrees preoperatively and passed to 12 degrees in the short fusion group, while changed from 45 degrees to 10 degrees in the long fusion group. Lumbar lordosis was 45 degrees preoperatively and 60 degrees at final follow-up in the short fusion group passed from 24 degrees to 55 degrees in the long fusion group. Sacral slope passed from 25 degrees to 45 degrees in the short fusion group, while from 10 degrees to 40 degrees in the long fusion group. Pelvic tilt passed from 24 degrees to 13 degrees in the short fusion group, and from 28 degrees to 23 degrees in the long fusion group. Conclusion Surgical treatment of degenerative lumbar scoliosis improved balance and alignment of the spine, and also the coronal plane in terms of Cobb angle. These results were associated to a consistent clinical improvement and an acceptable rate of complications.