LAUSR

OBJECTIVE To compare perioperative outcomes, PROMs, and minimum clinical important difference (MCID) achievement following single-level TLIF in patients stratified by preoperative comorbidity burden. METHODS PROMs were administered preoperatively/postoperatively and included Patient-Reported Outcomes Measurement Information System-Physical Function (PROMIS-PF), Visual Analogue Scale (VAS), Oswestry Disability Index (ODI), and 12-Item Short Form Physical Composite Score (SF-12 PCS). Patients were grouped: preoperative CCI score<5 (mild to moderate comorbidity) or preoperative CCI score≥5 (Severe preoperative comorbidity). A 3:1 propensity score match for age, gender, insurance status, smoking status, and preoperative spinal pathology was utilized to control for significant demographic differences between cohorts. RESULTS Following propensity score match, 255 patients were included (135 in CCI score<5 cohort; 120 in CCI score≥5 cohort). CCI score≥5 cohort demonstrated significantly reduced postoperative VAS back pain on the day of surgery(p<0.001, all). Mean PROM differences were noted for postoperative PROMs: VAS back and ODI 6-months, both instances favoring CCI≥5 cohort(p<0.038). CCI score<5 cohort improved from baseline to 1-year for all postoperative PROMs except SF-12 PCS 6-weeks and 12-weeks and SF-12 MCS 6-weeks(p<0.034, all). CCI score≥5 cohort reported significant improvement from preoperative baseline to the 1-year for all postoperative PROMs except ODI 6-weeks, SF-12 MCS 6-weeks and 1-year, SF-12 PCS 6-weeks, and PROMIS-PF 6-weeks(p<0.017, all). Both cohorts reported greater than 50% overall MCID achievement rate for VAS leg, VAS back, ODI, SF-12 PCS, and PROMIS-PF. CONCLUSION The results suggest that patients undergoing MIS-TLIF with severe comorbidities can expect similar postoperative trajectory for disability, leg and back pain, and physical function. However, long term (1-year) mental health improvement from preoperative baseline was only noted in the mild to moderate comorbid group.