Impact of preoperative back pain severity on PROMIS outcomes following minimally invasive lumbar decompression

Purpose To evaluate the effect of baseline back pain severity on PROMIS mental health outcomes following minimally invasive lumbar decompression (LD). Methods Patients undergoing elective, primary, single-level LD were retrospectively reviewed from a prospective single spine surgeon registry. Perioperative characteristics, demographics, and the following patient-reported outcomes (PROs) were extracted: Oswestry Disability Index (ODI)/Patient-Health Questionnaire-9 /PROMIS-Physical Function/Anxiety/Pain Interference/Sleep Disturbance (PROMIS-PF/A/PI/SD). Two cohorts were created: preoperative VAS-B < 7 and VAS-B >= 7. Change in PROs (Delta PROs) from baseline to six weeks/final follow-up were determined. Average patient follow-up was 13.4 +/- 8.8 months. Minimal clinically important difference (MCID) achievement rates were calculated and compared through multivariable logistic regression. Postoperative scores and Delta PROs, were compared with multivariable linear regression while all other data was compared between groups with inferential statistics. Results Altogether, 347 patients were included, with 190 in the VAS-B < 7 group. VAS-B >= 7 reported worse outcomes preoperatively (p <= 0.013, all). At six weeks, VAS-B >= 7 reported worse VAS-B (p = 0.017), with no other significant differences. At final follow-up, patients with worse VAS-B reported worse ODI (p = 0.040) and VAS-B while all other PROs were similar (p >= 0.078, all). VAS-B >= 7 experienced greater 6-week improvements in VAS-B/ODI/PROMIS-PI/PROMIS-SD (p <= 0.009, all), greater VAS-B/ODI/PROMIS-SD improvement by final follow-up (p <= 0.009, all) and greater MCID achievement in ODI/VAS-B (p <= 0.027). ConclusionPatients with worse baseline back pain report inferior baseline scores that converge with those with milder preoperative back pain by 6 weeks after LD and reported greater 6-week improvements in disability, pain interference, and sleep disturbance by 6 weeks, and greater improvements in disability and sleep disturbance by final follow-up.