Introduction: Adjacent segment disease (ASD) occurs in up to 18.5% of patients who undergo lumbar spinal fusion. Few studies have examined outcomes after surgical management of ASD, but a reoperation rate of 14% has been reported. The goal of this study was to determine the reoperation rate as well as risk factors for additional surgery following surgery for ASD.
Methods: A retrospective analysis of a consecutive series of 84 procedures for lumbar adjacent segment disease was performed. Odds ratios were calculated for potential risk factors for additional surgery after the ASD operation. Statistical significance was set at p< 0.05 and determined by Chi-squared test for categorical variables and student’s t-test for continuous variables.
Results: 14 patients (16.7%) required reoperation following surgery for ASD. The average follow-up time was 61.3 months. Decompression without fusion (OR 3.75, 95% CI: 1.07 - 13.15, p = .04) and a past history of spinal trauma (OR 3.56, 95% CI: 1.04 - 12.16, p = .04) were significantly associated with an increased risk for additional surgery. Gender, age, smoking history, location of adjacent segment pathology, and instrumentation of the index fusion were not significantly associated with reoperation.
Conclusions: Surgery for lumbar ASD is associated with a reoperation rate of 16.7%, which is similar to a previously reported result. Patients who underwent decompression without extension of the index fusion and those with a past history of spinal trauma were found to be at increased risk for additional surgery after surgical management for ASD. Reoperation is an important source of postoperative morbidity and this data will be useful in the preoperative counseling of patients undergoing surgical management of ASD.
Patient Care: This data on postoperative morbidity will be useful in the preoperative counseling of patients undergoing surgical management of adjacent segment disease in the lumbar spine.
Learning Objectives: Understand the significance of various risk factors for reoperation associated with surgical management of adjacent segment disease in the lumbar spine.