Elderly Patients Achieving Clinical and Radiological Outcomes Comparable with Those of Younger Patients Following Minimally Invasive Transforaminal Lumbar Interbody Fusion.

STUDY DESIGN: Retrospective analysis of prospective database.

PURPOSE: To compare 2-year clinical and radiological outcomes after minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) among "middle-age" (50-64.99 years), "young-old" (65-74.99 years), and "old-old" (>75 years) patients.

OVERVIEW OF LITERATURE: Owing to higher perioperative morbidity and mortality rates, elderly patients with degenerative lumbar conditions are occasionally denied surgical care, even after conservative treatment failure. MIS-TLIF advantages include reduced blood loss, reduced analgesia requirements, early mobilization, and shorter hospital stays.

METHODS: Between 2007 and 2012, 22 patients (age >75 years) treated with 1-2 level MIS-TLIF were matched with "young-old" and "middle-age" patients (22 each) based on race, body mass index (BMI), diagnosis, spinal level, number of spinal levels operated upon, and bone graft type. Clinical outcomes included the Oswestry disability index (ODI), neurogenic symptom score (NSS), 36-item short form health survey (SF-36), and visual analogue scale (VAS) for back and leg pain. Radiological assessment included plain radiographs and preoperative magnetic resonance imaging (MRI) and plain radiographs at 1, 3, 6, and 24 months postoperatively. Fusion grade, loosening, cage migration, and adjacent segment degeneration were assessed.

RESULTS: The groups had similar fluoroscopy time, operation duration, and postoperative analgesia type used. "Old-old" patients took longer to ambulate (1.6 days) and had longer hospital stays (6 days). All patients showed significant improvement in clinical outcome scores at all time-points compared with the preoperative status. "Middle-age" patients showed better ODI and SF-36 physical function scores than "old-old" patients preoperatively and 2 years post surgery. NSS, VAS (back and leg), and SF-36 mental function scores were similar between groups preoperatively and at every time-point postoperatively. Minimal clinical important differences (63.6%-95.5% at 2 years) were achieved. Grade 1 fusion occurred in a minimum of 80% patients in each group 2 years post surgery. Complication rates were similar. Adjacent segment disease occurred in 2 patients from the "young-old" group, with no significant differences between groups.

CONCLUSIONS: MIS-TLIF showed comparable results in selected "old-old" patients compared with "young-old" and "middle-age" patients without increased complication risks.