The Effect of the Severity of Preoperative Disability on Patient-Reported Outcomes and Patient Satisfaction Following Minimally Invasive Transforaminal Lumbar Interbody Fusion

OBJECTIVE: To compare patient-reported outcomes (PROMs), satisfaction, and minimum clinically important difference (MCID) achievement following minimally invasive transforaminal lumbar interbody fusion stratified by preoperative disability. METHODS: Minimally invasive transforaminal lumbar interbody fusions were grouped by preoperative Oswestry Disability Index (ODI) score: ODI <41 or ODI >= 41. PROMs administered pre/postoperatively included Patient-Reported Outcomes Measurement Information System physical function (PROMIS-PF), visual analog scale (VAS) back/leg, ODI, and 12-Item Short-Form Physical Composite Score (SF-12 PCS)/12-Item Short-Form Mental Composite Score (SF-12 MCS). Satisfaction scores were collected for VAS back/leg and ODI. Coarsened exact match controlled for differences between cohorts. T tests compared mean PROMs and postoperative improvement/satisfaction between cohorts. Simple logistic regression compared MCID achievement. RESULTS: After coarsened exact matching, there were 118 patients in the ODI <= 41 and 377 patients in the ODI >41 cohort. The ODI >41 cohort saw greater postoperative inpatient VAS pain score and narcotic consumption on days 0/1 (P < 0.018, all). PROMs differed between cohorts: PROMIS-PF, SF-12 PCS, ODI, VAS back/leg at all postoperative time points and SF-12 MCS at 6 weeks/12 weeks/6 months/1 year (P < 0.045, all). Patients in the ODI >41 cohort demonstrated greater proportion achieving MCID for ODI at all postoperative time points and for SF-12 MCS 6-week/12-week/6-month/1-year (P < 0.040, all). The ODI <= 41 cohort demonstrated greater MCID achievement for overall PROMIS-PF and SF-12 PCS 6 months (P < 0.047, all). Postoperative satisfaction was greater in the ODI <= 41 cohort for VAS leg 6 weeks/12 weeks, VAS back 6 weeks/12 weeks, and ODI all postoperative time points (P < 0.048, all). CONCLUSIONS: Preoperative disability associated with worse postoperative PROMs and patient satisfaction for disability, back/leg pain at multiple time points. MCID achievement rates across cohorts were similar for most PROMs at most postoperative time points. Patients with severe disability may have unrealistic expectations for surgical benefits, influencing corresponding postoperative satisfaction.