Women Do Not Have Poorer Outcomes After Minimally Invasive Lumbar Fusion Surgery: A Five-Year Follow-Up Study.

BACKGROUND Women undergoing lumbar spine surgery report greater preoperative pain and disability and have less improvement after surgery. There is a paucity of literature on sex-related differences after minimally invasive surgery transforaminal lumbar interbody fusion (MIS TLIF) surgery. We aim to determine whether sex influences outcome after MIS TLIF at 5-year midterm follow-up. METHODS Prospectively collected registry data for 907 patients who underwent MIS TLIF at a single institution from 2004 to 2013 were reviewed. Of these, 296 patients (94 males and 202 females) were reviewed at 5-year follow-up. All patients were assessed preoperatively and postoperatively at 2 and 5 years. Data recorded included patient demographics, Oswestry Disability Index (ODI), Short-Form 36 Physical and Mental component scores (SF-36 PCS and MCS), and the North American Spine Society lumbar spine outcome assessment instrument. RESULTS Females who underwent MIS TLIF were generally younger (females, 52.2 years; males, 56.1 years; P = .04). Females had significantly poorer preoperative ODI (females, 49.5; males, 41.5; P < .001) and SF-36 PCS (females, 31.9; males, 35.6; P < .01) and MCS (females, 44.9; males, 49.2; P < .01) scores. At 2-year and 5-year follow-up, there were no significant differences in ODI, SF-36, and pain scores between sexes. Both groups reported similar proportions that returned to work and returned to function. There were no differences in proportion of patients who were satisfied or had their expectations fulfilled. CONCLUSIONS Women who undergo MIS TLIF have poorer preoperative function and quality of life than men. However, women demonstrated greater improvement after surgery, attaining similar clinical outcomes at 5-year follow-up. LEVEL OF EVIDENCE 3.