Re-operation After Surgery for Grade 2 and 3 Lumbar Spondylolisthesis: An Analysis of the Quality Outcomes Database

Introduction: Surgical intervention for grade 2- and 3-spondylolisthesis is technically challenging. Due to the degree of slippage, complications including need for reoperation may be higher in these patients compared to low grade 1 spondylolisthesis. Few studies have assessed rates and reasons for re-operation in a large multi-center cohort of patients.

Methods: We performed a retrospective, multicenter analysis of the prospectively maintained Quality Outcomes Database (NeuroPoint Alliance). Patients who underwent surgical intervention for lumbar grade 2- or 3-spondylolisthesis were identified, and 383 patients met inclusion criteria. Univariate analysis was performed between patients without and with revision surgery. Variables with p< 0.2 were included in a multivariate analysis.

Results: The average age was 60 years (range 23-88). Patients were largely female (70.2%) and had predominantly grade 2-spondylolisthesis (93.2%). The majority underwent primary surgery (85.9%). Follow-up rate at 2 years or longer was 84%. Twenty-three (6.0%) patients underwent a total of 31 revision surgeries. Reasons for revision were adjacent segment disease (35.5%), same-level hardware failure (19.4%), infection (19.4%), nerve palsy (6.5%), and CSF leak (3.2%). Patients who required revision had a higher BMI, ASA scores, ODI scores, more likely to have a post-op complication or readmission, and less likely to be independently ambulatory. On multivariate analysis, the predictors of re-operation were having a hematoma (OR 34.7; CI 2.3-526; p=0.01) within 30 days or being readmitted within 90 days (OR 12.4; CI 2.7-55.8; p=0.001). Readmissions at 90 days were largely secondary to infection and wound dehiscence.

Conclusion : Overall re-operation rates were low after surgical treatment of mid-grade spondylolisthesis. The most common reason for revision surgery was adjacent segment disease. Not surprisingly, complications such as hematoma and early readmission significantly predicted reoperation; however, no predictors for longer-term complications such as adjacent segment disease were found.