Study design:

Retrospective cohort.

Objective:

We evaluate the correlation of the Patient Reported Outcomes Measurement Information System for physical function (PROMIS-PF) with legacy patient reported outcome measures (PROMs) in patients undergoing minimally invasive transforaminal lumbar interbody fusion (MIS TLIF) up to 2-years postoperatively.

Summary of background data:

PROMIS-PF not been validated past 6-months following MIS TLIF.

Methods:

A surgical registry was retrospectively reviewed for eligible MIS TLIFs between May 2015 to September 2017. Inclusion criteria were primary, 1- or 2-level MIS TLIFs for degenerative spinal pathology. Patients without preoperative or 2-year follow up PROMIS-PF surveys were excluded. Demographic, perioperative, and PROM including Visual Analog Scale (VAS) back, VAS leg, Oswestry Disability Index (ODI), 12-Item Short Form (SF-12) physical component summary (PCS) scores and PROMIS-PF at preoperative and postoperative timepoint (e.g. 6-weeks, 12-weeks, 6-months, 1-year, and 2-years). A paired t-test evaluated PROM improvement from baseline. The relationship of PROMIS-PF with VAS back, VAS leg, SF-12 PCS, and ODI was evaluated with a Pearson’s correlation coefficient.

Results:

The 68 subject cohort was 41.2% female, with an average age of 52.9. 44.1% were obese, and the majority underwent 1-level fusions (95.6%). Pain (VAS back, VAS leg) and disability metrics (ODI) demonstrated significant improvement at all timepoints following MIS TLIF when compared to baseline (all p < 0.001). Physical function (SF-12 PCS, PROMIS-PF) demonstrated significant postoperative improvement at 12-weeks, 6-months, 1-year, and 2-years (all p < 0.001). All evaluated timepoints, with the exception of preoperative VAS back scores, revealed strong PROMIS-PF correlations with VAS back, VAS leg, ODI, and SF-12 PCS.

Conclusion:

PROMIS-PF demonstrated a strong correlation with pain (VAS back, VAS leg), disability (ODI) and physical function (SF-12) at all postoperative follow-ups through 2-years. Our study provides longitudinal evidence for utilizing PROMIS-PF as a valid physical function measure among patients undergoing MIS TLIF.

Level of evidence:

4.