Lightning Podiums: Smorgasboard - Room 802B

Presented by: S.-G. Lee


S.-G. Lee(1), T.-K. Lim(1), Y. Ahn(1), S. Son(1), T.S. Jeong(1), W.-K. Kim(1)

(1) Gachon University, Gil Medical Center, Neurosurgery, Incheon, Korea, Republic of


Object: Posterior dynamic stabilization (PDS) in degenerative lumbar stenosis is one of the treatment options. Unlike spinal fusion, PDS has been expected to preserve fixed vertebral segment motion. Therefore, it is thought that PDS can prevent complications such as adjacent segment degeneration. However, the long-term prognosis of PDS remains questionable. In this study, long-term (at least 10 years) results and radiological changes were analyzed and the efficacy of PDS was studied.

Methods: Twenty-five patients were followed up for more than 10 years with PDS as "Interspinous U" in single level lumbar stenosis. We evaluated clinical findings and simple plain X-ray and stress view of these patients. We collected postoperative 5-year and last follow-up data on Odom criteria, Oswestry disability index (ODI), complications, segmental degeneration, and instability. Total lumbar spine and segmental lordotic angles were calculated during the 5 years and last follow - up period.

Results: The mean age of the patients was 55.9 ± 15.6 years. The mean follow-up period was about 10.6 years. There were 9 good outcome groups and 16 patents in the other group. Ten patients (40%) showed instability after the last follow-up. Eight patients (32%) received reoperation. Three patients underwent fusion surgery and the other patients underwent simple decompression at the adjacent level. However, many patients with bone erosion showed good clinical outcomes due to union at the final follow-up. In the last follow-up, trend instability (p = 0.01) and adjacent segment degenerative (p = 0.05) were higher in poor results. The changes of total lumbar spine and torsion angle were not statistically different between the two groups at 5 years and last follow - up.

Conclusion: More than 10 years follow - up to PDS has shown radiographic degeneration and instability. Clinical results were not good. PDS still has limitations in motion preservation and good clinical outcomes through long-term follow-up in the treatment of degenerative lumbar stenosis.