Tehran University Medical Journal

Background: Degenerative spondylolisthesis is a common disease of the lumbar spine especially in older ones. The disease represents a challenge to the treating physician. At present, for those patients that deteriorate clinically, there are many proposed algorithms for the surgical treatment. This before and after study was undertaken to assess the surgical results of decompression and instrumented posterolateral fusion in these patients.

Methods: The study population consisted of 23 patients who had undergone no prior surgery for degenerative spondylolisthesis on the lumbar spine. These patients were treated by decompression, bilateral posterolateral fusion, and segmental (pedicle screw) instrumentation with mean follow-up of 29 months (range, 13-73 months). Finally, The clinical results were evaluated for all patients by means of an Oswestry Disability Index (ODI) version 2.1, the Henderson's functional capacity, and persistence of leg symptoms, low back pain or claudication. Mann-Whitney and Chi-Square tests were used to assess the average values and comparison, respectively.

Results: Henderson's functional capacity at the last visit session was excellent in 14 (60.9%), good in 7 (30.4%), fair in 2 (8.7%) cases. ODI decreased from 72.2% (50-88%) preoperatively to 14.4% (0-54%) at the latest follow-up visit. A history of leg pain or claudication was correlated significantly with the amount of decline in ODI score and Henderson's functional capacity (p<0.05).

Conclusion: In spite of limited number of our patients, decompressive surgery plus instrumented posterolateral fusion is a safe, reliable, and satisfactory procedure for treating degenerative lumbar spondylolisthesis. This procedure may be done when conservative treatment was failed and psychological problems can be ruled out.

Background: Severe spondylolisthesis is related to high degenerative changes in verte-bral spine. Degenerative spondylolisthesis often is seen with high-sacral slope. This study was conducted to investigate the relationship between high degenerative spondyl-olisthesis and sacral slope.
Methods: A cross-sectional prospective study was done in patients with low back pain in Shafa Yahyaian and Sina University Hospitals in Tehran, in 18 months (April 2010- October 2011). Intermittent or continuous low back pain for three months and history of two disable low back pain attacks since one year ago were inclusion criteria. Pregnant patients were excluded. Lumbar vertebra displacement to vertebra body size ratio was calculated in dynamic mode. The ratio higher than 8% was considered as a lumbar instability. Rotation angle more than 11 ° was considered abnormal.
Results: In this study, 52 patients (30 men, 22 women) with 38.35±9.49 years old were enrolled. Mean body mass index was 23.01±4.59kg/m2. Thirty cases had abnormal verte-bral displacement. Angulation of the disc space more than 11 degrees was seen in 20 patients. No statistically significant difference in pelvic index between normal and abn-ormal lumbar vertebra displacement (P=0.443). The mean pelvic index in normal and abnormal angulation groups were 55.97° and 53.58°, respectively the difference was not statistically significant (P=0.556).
Conclusion: The results of the study showed disc degeneration had no association with sacral slope. High sacral slope can intensify spondylolisthesis but does not affect the incidence of degenerative spondylolisthesis. Additional research is required to find the other causes of degenerative spondylolisthesis.