Multiple-Repeated Adjacent Segment Disease After Posterior Lumbar Interbody Fusion

Although posterior lumbar interbody fusion (PLIF) has provided satisfactory clinical outcomes, adjacent segment disease (ASD) is one of the most important complications affecting long-term results. However, according to ASD studies, few have described repeat surgery. The purpose of this study was to elucidate incidence, time period, and clinical features of multiple-repeated ASD after PLIF. Subjects comprised 1112 consecutive patients (502 men, 610 women) who underwent 1-level PLIF for degenerative lumbar diseases. The mean age of patients was 66 years (range, 15–89). The mean follow-up period was 6.4 years (range, 0.5–21.1). The incidence and the time period of multiple-repeated ASD were investigated. To elucidate clinical features of the multiple-repeated ASD, all 4 cases were shown as the case description including radiographic parameters. Four (0.4%) developed multiple-repeated ASD: 3 women and 1 man. Primary PLIF was performed at L3-4 in 1 patient and at L4-5 in 3 patients. Two patients underwent adjacent segment decompression simultaneously. All patients required at least 3 additional surgeries due to newly occurred ASD after each PLIF. All patients developed iatrogenic flatback as ASD was repeated. As a result, corrective surgeries were required (thoracolumbar, 2; spinopelvic, 2). Multiple-repeated ASD was observed in 0.4% of the patients. All patients developed iatrogenic flatback as a result of repeated ASD, and corrective surgeries were required for these patients. •Of 1321 patients who underwent PLIF, 4 (0.3%) developed multiple-repeated ASD.•All 4 patients showed insufficient segmental lordosis after first PLIF.•Surgeons should endeavor to achieve adequate segmental lordosis at the first PLIF.