Single Surgeon Experience of Adjacent Segment Disease and Related Risk Factors Following Posterior Decompression and Fusion in Lumbar Degenerative Disorders

Background and Aim: This study aims to evaluate the frequency of adjacent segment disease (ASD) and its risk factors following posterior decompression and fusion in lumbar degenerative disorders. Methods and Materials/Patients: This retrospective cohort study was performed by reviewing the records of patients with spinal degeneration disorders who underwent lumbar fusion surgery and needed reoperation from 2013 to 2019. The participants were divided into two groups, including patients with ASD and non-ASD patients, and were compared in terms of age, sex, BMI, smoking, fusion level, surgical indications, follow-up times, laminectomy, cross-link device usage, imaging findings, fusion terminating in L1, L5 and S1, and reoperation. Results: Out of a total of 277 candidates, 181 met the inclusion criteria. In terms of gender distribution, 43.3% of the participants were male and 56.7% were female. The median age was 54 years in the ASD group and 48 years in the non-ASD group. The median follow-up of the patients was six years in the ASD group and five years in the non-ASD group. Forty patients (22.1%) developed ASD during this period. The final analysis showed a significant relationship between age, sex, indication for reoperation, repeated surgery, laminectomy, cross-link device use, imaging findings, and fusion terminating in L1. Conclusion: High body mass index, aging, lumbar spinal canal stenosis, reoperation, laminectomy at the upper fusion unit, cross-link device use, lumbar canal stenosis in imaging, and fusion to L1 vertebrae are considered risk factors for ASD.