Can patients with sagittally well-compensated lumbar degenerative kyphosis benefit from surgical treatment for intractable back pain?

Objective: To analyze pre- and postoperative x-rays of sagittal spines and to review the surgical results of 21 patients with lumbar degenerative kyphosis whose spines were sagittally well compensated by compensatory mechanisms but who continued to suffer from intractable back pain

Methods: We performed a retrospective review of 21 patients treated with combined anterior and posterior spinal arthrodesis. Inclusion criteria were: lumbar degenerative kyphosis patients with intractable back pain and whose spines were sagittally well compensated by a compensatory mechanism, defined as a C7 plumb line to the posterior aspect of the L5-S1 disc of less than 5 cm. Outcome variables included: radiographic measures of preoperative, postoperative, and follow-up films; clinical assessment using the mean Numeric Rating Scale, Oswestry Disability Index, and Patient Satisfaction Index; and a review of postoperative complications.

Results: All patients were female (mean age, 64.5 years; age range, 50-74 years). The mean preoperative sagittal imbalance was 19.5 (+/- 17.6) mm, which improved to -15.8 (+/- 22.2) mm after surgery. Mean lumbar lordosis was 13.2 degrees (+/- 15.3) before surgery and increased to 38.1 degrees (+/- 14.4) at follow-up (P < 0.0001). Mean thoracic kyphosis was 5.5 degrees (+/- 10.2) before surgery and increased to 18.9 degrees (+/- 12.4) at follow-up (P < 0.0001). Mean sacral slopes were 12.9 degrees (+/- 11.1) before surgery and increased to 26.3 degrees (+/- 9.6) at follow-up (P < 0.0001). The mean Numeric Rating Scale score improved from 7.8 (back pain) and 8.1 (leg pain) before surgery to 3.0 (back pain) and 2.6 (leg pain) after surgery (P < 0.0001). The mean Oswestry Disability Index scores improved from 56.2% before surgery to 36.7% after surgery (P < 0.0001). In 18 (85.5%) of 21 patients, satisfactory outcomes were demonstrated by the time of the last follow-up assessment.

Conclusion: This study shows that even lumbar degenerative kyphosis patients with spines that are sagittally well compensated by compensatory mechanisms may suffer from intractable back pain and that these patients can be treated effectively by the restoration of lumbar lordosis.