Does Gender Influence Postoperative Outcomes in Minimally Invasive Transforaminal Lumbar Interbody Fusion?

Study Design: Retrospective cohort.

Objective: The objective of this study was to determine if an association exists between gender and postoperative improvements in patient-reported outcomes (PRO) measures following minimally invasive transforaminal lumbar interbody fusion (MIS TLIF).

Summary Of Background Data: Current spine literature presents conflicting findings regarding the influence of gender on clinical outcomes.

Methods: Patients undergoing primary, single-level MIS TLIF were retrospectively reviewed. PRO measures including Oswestry Disability Index (ODI) and Visual Analog Scale (VAS) back and leg pain scores were collected preoperatively and 6-week, 12-week, and 6-month postoperatively. Rates of minimum clinically important difference (MCID) achievement were determined at 6-months postoperative. Statistical analysis was performed using Pearson χ analysis or Student t test.

Results: In total, 169 patients, 40.83% females and 59.17% males, were included. Females experienced greater inpatient pain scores than males (POD 0: 5.30 vs. 4.69, P=0.041; POD 1: 4.80 vs. 4.13, P=0.019). Females demonstrated significantly greater ODI (43.77 vs. 36.22; P=0.002) and VAS leg (6.20 vs. 5.27; P=0.039) scores than males. No differences in postoperative improvements in ODI, VAS back or VAS leg pain scores were identified between genders, with exception to females demonstrating greater improvement in VAS leg pain at 6 months postoperatively (female: -4.40 vs. male: -3.32; P=0.033). Furthermore, no differences in MCID achievement for PROs were identified between cohorts.

Conclusions: Females demonstrated greater preoperative pain and disability as well as inpatient VAS pain scores compared to males. Furthermore, gender was not associated with differences in length of stay, perioperative complication rates, or narcotics consumption. Improvements in pain and disability, as well as rates of MCID achievement were similar between genders. These findings suggest that gender is not associated with surgical or clinical outcomes and should not be used as a predictor of outcomes following MIS TLIF.

Level Of Evidence: Level III.