Long-Term Results of Minimally Invasive Transforaminal Lumbar Interbody Fusion in Elderly Patients: A 5-Year Follow-Up Study

Study design: Retrospective review of prospective data.Objectives: Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) may be beneficial for elderly patients due to decreased surgical morbidity and faster postoperative recovery. This study compared the clinical and radiological outcomes of MIS-TLIF in elderly patients and younger controls at minimum 5-year follow-up.Methods: There were 120 patients who underwent single-level MIS-TLIF for degenerative spondylolisthesis. Elderly patients (>= 70 years; n = 30) and controls (<70 years; n = 90) were matched 1:3 for demographics, comorbidities and preoperative patient-reported outcomes (PROs). The Oswestry Disability Index (ODI), 36-Item Short-Form Physical (SF-36 PCS) and Mental Component Summary (SF-36 MCS), Visual Analogue Scale (VAS) back pain, and VAS leg pain were compared at 6 months, 2 years and 5 years. Radiographic fusion, adjacent segment degeneration (ASD) and revision rates were assessed at mean 7.2 +/- 2.0 years.Results: Elderly patients had longer length of stay (4.7 +/- 5.8 vs 3.3 +/- 1.4 days, P = .035) and more readmissions (10% vs 1%, P = .019), but there was no difference in operative time, transfusions, complications or discharge disposition. All PROs were comparable at 5 years and satisfaction rates were similar (93% elderly vs 91% controls, P = .703). The rates of radiographic fusion in the control group and elderly group were similar (94% vs 97%, P = .605), as were the rates of ASD (40% vs 33%, P = .503). There were 3 revisions (3.3%) in the control group (2 for ASD, 1 for screw loosening) but none in the elderly group (P = .311).Conclusions: Elderly patients undergoing MIS-TLIF achieved similar improvements in pain, disability and quality of life that were sustained at 5 years.Level of Evidence: Level III, retrospective cohort study.