Differences in Clinically Important Physical Function Improvement in Workers' Compensation Population.

Abstract

Patients receiving workers' compensation demonstrate a propensity for poorer postoperative outcomes. This study aims to determine rates of minimum clinically important difference (MCID) achievement in patients receiving workers' compensation following transforaminal lumbar interbody fusion (TLIF). We retrospectively reviewed a prospective surgical database from 2015 to 2020 for primary, single-level TLIFs with posterior instrumentation for degenerative spinal pathologies. Visual analog scale (VAS) for back and leg, Oswestry Disability Index (ODI), 12-Item Short Form Physical Component Summary (SF-12 PCS), and Patient-Reported Outcome Measurement Information System physical function (PROMIS-PF) were collected pre- and postoperatively. Patients were separated by workers' compensation (WC) status. Propensity score matching was performed to account for differences in demographic characteristics. Postoperative improvements in patient-reported outcome measures (PROMs) were calculated using paired Student's t test, and intergroup differences were determined by Mann-Whitney U test. Achievement of MCID was determined using established values, and intergroup differences were assessed using χ 2 analysis. A total of 121 patients were included in this study with 29 WC and 92 non-WC patients. The mean age was 53.5 years with the majority being men (63.6%) and nonobese (54.5%). WC patients demonstrated significantly poorer PROM values at all timepoints except for preoperative VAS back (P = 0.297) and leg (P = 0.475). Overall achievement of MCID was significantly lower for WC patients for VAS back (P = 0.040), ODI (P = 0.001), SF-12 PCS (P = 0.010), and PROMIS-PF (P = 0.039). WC patients demonstrated poorer postoperative outcomes at multiple timepoints. Additionally, a significantly lower rate of MCID achievement for back pain, disability, and physical function was observed for WC patients. These results suggest that WC patients may require alternative preoperative counseling about realistic expectations for improvement following lumbar fusion.