Evaluation of Spinal Instability after Single Level Fenestration Discectomy: A Prospective Study

Abstract

Introduction: Failed back surgery syndrome (FBSS) represents a clinical condition of patients that undergo one or more surgical procedures for lumbosacral disease and still present unsatisfactory long-term relief of symptoms, with persistent or recurrent low back pain. One of the sources of failed back surgery syndrome is segmental instability of the lumbar spine. There is very limited evidence in the literature regarding the incidence of spinal instability following fenestration and discectomy. Materials and Methods: This study was conducted on 50 patients who were between 17 and 52 years and who had undergone fenestration discectomy for a single-level lumbar intervertebral disc prolapse. Results: Results were evaluated using Prolo economic and functional outcome scoring which showed good outcome in 41 (82%) patients and moderate outcome in 9 (18%) patients after fenestration. Clinical instability as per criteria was noted in 9 (18%) patients post operatively while radiological instability was noted in 1(2%) patient . All 9 (100%) patients with clinical instability showed a moderate outcome. 13(26%) patients showed a decrease in the disc height more than 30% as compared with there preoperative images before lumbar fenestration. Patients with radiological sign of instability showed a good outcome. Conclusion: Standard fenestration discectomy does not destabilize the spine. Further studies are required to truly evaluate the development and progression of segmental instability in patients treated for lumbar disc herniation using different surgical methods.