Clinical and Radiographic Outcomes of Lateral Interbody Fusion for Adjacent Segment Degeneration

Study Design: Retrospective cohort study. Objective: Assessment of outcomes in patients undergoing lateral interbody fusion as part of the surgical treatment of adjacent segment deterioration after previous lumbar spine fusion. Methods: Adult patients with previous lumbar posterior spinal fusion who presented with adjacent segment degeneration and stenosis refractory to nonoperative treatment and who underwent lateral lumbar interbody fusion were retrospectively analyzed. Clinical and radiographic outcomes were assessed and comparisons made between preoperative baseline and postoperative values. Results: Thirty-six patients with symptomatic adjacent segment degeneration at 46 motion segments were included. Thirty (83.3%) of the 36 patients had complete relief of both preoperative lower extremity pain and back pain at the time of final follow-up. Six (16.7%) of the 36 patients had persistent pain, though in all 6 cases, the pain was less postoperatively than preoperatively. Oswestry Disability Index scores were improved significantly at final follow-up (P = .001). Compared with preoperative baseline parameters, initial and final postoperative radiographs had an increase in segmental lordosis (P < .001 and P < .001, respectively), increase in overall lumbar lordosis (P < .05 and P = .094, respectively), decrease in segmental coronal angulation (P = .63 and P < .01, respectively), decrease in overall coronal angulation (P = .063 and P = .009, respectively), and increase in intervertebral height (P < .001 and P < .001, respectively). Conclusion: Lateral lumbar interbody fusion achieves favorable clinical and radiographic outcomes for the treatment of adjacent segment degeneration after previous lumbar fusion. Level of Evidence: 4.