A Surgical Treatment of Low-Grade Spondylolisthesis: A Comparative Study of in Situ Fusion and Fusion after Reduction

ABSTRACT

OBJECTIVE: This study retrospectively analysed the influence of reduction to postoperative symptoms in 57 patients with low-grade degenerative or ishmic spondylolisthesis managed with posterolateral fusion delete. PATIENTS AND METHODS: The clinical and radiological severity were assessed with Prolo's grade(economic and functional) and static and dynamic lateral radiographs(displacement and angulation). The postoperative questionnaire and the change of translation and angulation of static and dynamic lateral radiographs were used to judge the clinical and radiological success. All patients were treated with decompression and stabilization with instrumentation and autologous bone fusion, with or without reduction. The patients were followed clinically for a mean of 693.11 days (range, 6 to 18 months). RESULTS: There were 32 cases of spondylolytic spondylolisthesis, and the remaining 25 cases were degenerative spondylolisthesis. The average Prolo's economic grade delete of 20 patients delete managed without reduction was not statistically different from that delete of 37 patients managed with reduction(4.20 vs. 4.24, p>0.01). Also, the average Prolo's functional grade delete of 20 patients managed without reduction was not statistically different from delete of 37 patients managed with reduction(4.05 vs. 3.97, p>0.01). CONCLUSIONS: The authors conclude that in situ stabilization using autologous posterolateral arthrodesis combined with pedicular screw fixation resulted a good outcome. The additional procedure of reduction, performed with decompression and instrumented posterolateral fusion, for the treatment of the patients with low-grade degenerative and isthmic spondylolisthesis does not appear to provide additional benefits on functional outcome.