Incidence of revision surgery and patient-reported outcomes within 5 years of the index procedure for grade 1 spondylolisthesis: an analysis from the Quality Outcomes Database spondylolisthesis data.

Objective: Some patients treated surgically for grade 1 spondylolisthesis require revision surgery. Outcomes after revision surgery are not well studied. The objective of this study was to determine how revision surgery impacts patient-reported outcomes (PROs) in patients undergoing decompression only or decompression and fusion (D+F) for grade 1 spondylolisthesis within 5 years of the index surgery.

Methods: Patients in the 12 highest Quality Outcomes Database (QOD) enrolling sites with a diagnosis of grade 1 spondylolisthesis were identified and the incidence of revision surgery between the decompression-only and D+F patients were compared. PROs were compared between cohorts requiring revision surgery versus a single index procedure.

Results: Of 608 patients enrolled, 409 had complete 5-year data available for this study. Eleven (13.3%) of 83 patients underwent revision in the decompression-only group as well as 32 (9.8%) of 326 in the D+F group. For the entire cohort, patients requiring revision had significantly worse PROs at 5 years: Oswestry Disability Index (ODI) 27.4 versus 19.4, p = 0.008; numeric rating scale for back pain (NRS-BP) 4.1 versus 3.0, p = 0.013; and NRS for leg pain (NRS-LP) 3.4 versus 2.1, p = 0.029. In the decompression-only group, the change in 5-year PROs was not impacted by revision status: ODI 31.9 versus 24.2, p = 0.287; NRS-BP 1.9 versus 2.9, p = 0.325; and NRS-LP 6.2 versus 3.7, p = 0.011. In the D+F group, the change in 5-year PROs was diminished if patients required revision: ODI 19.1 versus 29.1, p = 0.001; NRS-BP 3.0 versus 4.0, p = 0.170; and NRS-LP 2.3 versus 4.6, p = 0.001.

Conclusions: The most common reasons for reoperation within 5 years in the decompression-only group were repeat decompression and instability, whereas in the D+F group the most common reason was adjacent-segment disease. The need for revision resulted in modestly diminished benefit compared with patients with no revisions. These differences were greater in the fusion cohort compared with the decompression-only cohort. The mean PRO improvement still far exceeded minimal clinically important difference thresholds for all measures for patients who underwent a revision surgery.