Abstract: Introduction: Literature evidence of outcome of reduction, spinal fusion through single stage posterior approach in patients of high-grade spondylolisthesis is lacking. Aim of the study, is to study the surgical outcome of High-grade spondylolisthesis patients, managed through single stage posterior approach.
Materials and Methods: We have retrospectively analysed high -grade spondylolisthesis adolescents and young adults of patients of age less than 30 years, who have undergone reduction and spinal fusion in our institute for the past 5 years with a follow-up of two years. 27 patients, who have undergone surgery in the time period between 2011 to 2016, were evaluated with preop standing lumbosacral radiograph for slip angle, L5 incidence angle, lumbar lordosis, slip percentage. Oswestry disability index [ODI] score for low back pain, neurological examination, sf-36 health survey questionnaire are the clinical parameters analysed. The patients who had undergone the surgery were followed up for 2 years and evaluated with standing radiographs for all the above radiological parameters, clinical parameters and assessment of spinal fusion by Bridwell criteria. Parameters were analysed statistically with SPSS software version 25.0. p less than 0.05 was considered statistically significant.
Results: The aim of the surgery is to reduce the L5-S1slip angle to less than 30 degrees, and not about the complete restoration of displacement of L5 over S1. Mean slip angle, L5 incidence angle, Lumbar lordosis, slip percentage changed from 41.57 to12.10 [p<0.01], 78.57 to 47.50[p<0.05], 81.40 to 55.5 degrees, 4.93 to 1.77 percent respectively. Change in slip angle, L5 incidence angle were statistically significant. ODI score improved from 71.17to 17.72. SF-36 health survey questionnaire showed superior results at follow-up and all the patients showed excellent fusion [Bridwell grade 1], no significant neurological complications were encountered at 2 years follow-up.
Conclusion: Surgical outcome of high-grade spondylolisthesis patients through single stage posterior approach produces superior results, at two years postoperatively, if intraoperatively slip angle is reduced to less than 30 degrees.
