Clinical StudyComparison of lumbar discectomy alone and lumbar discectomy with direct repair of pars defect for patients with disc herniation and spondylolysis at the nearby lumbar segment

Background contextIt is unknown whether direct repair (DR) of pars defect after lumbar discectomy (LD) for patients with lumbar disc herniation (LDH) and spondylolysis leads to better outcomes than LD alone.PurposeThe aim was to compare two surgical methods, LD alone and LD with DR, for LDH patients with spondylolysis at a nearby lumbar segment.Study designThis was a retrospective comparative study.Patient sampleThis study enrolled 89 patients who were diagnosed with LDH and spondylolysis at the same or adjacent lumbar segment and were followed up for at least 1 year.Outcome measureThe primary outcome was pain intensity of the lower back and lower extremities as measured with visual analog scale. Secondary outcomes included clinical outcomes as assessed with the Oswestry Disability Index and the 12-item short form health survey, radiologic outcomes as assessed with the gap distance and the union rate at the pars defect, surgical outcomes, and complications.MethodsEnrolled patients were classified into two groups: LD alone (Group A, 48 patients) and LD with DR (Group B, 41 patients).ResultsPain intensity of the lower back and lower extremities and clinical outcomes were significantly improved 1 year after surgery compared with preoperative scores. However, the scores in the group receiving LD alone steadily worsened during follow-up, whereas the scores in the group receiving LD with DR did not deteriorate over time. The difference in the gap distance of the pars defect between baseline and 1 year after surgery was significantly different between the groups. The fusion rate of the pars defect was 59% (24/41). With the exception of surgical time, which was longer in Group B, surgical outcomes and complications did not differ significantly between the groups.ConclusionsAt the 1-year follow-up, DR after LD was associated with better outcomes for LDH with spondylolysis than LD alone.