Does Preoperative Symptom Duration Impact Clinical Outcomes After Minimally Invasive Transforaminal Lumbar Interbody Fusion in the Ambulatory Setting?

BACKGROUND: The effect of prolonged symptom duration in patients undergoing ambulatory MIS-TLIF on postoperative clinical outcomes has not been well studied. We aim to compare symptom duration of pain and/or weakness on postoperative outcomes in patients undergoing outpatient MIS-TLIF. METHODS: Patients undergoing outpatient MIS-TLIF were gathered in a single-surgeon database. Exclusion criteria were patients missing onset of symptoms, date of surgery, or diagnosis of malignancy, trauma, or infection. Patients were grouped by symptoms <1 year or symptoms >= 1 year. Propensity score matching for demographics was utilized. Minimal clinically important difference (MCID) achievement was calculated by comparing change in patient-reported outcome measures (PROMs) to previously established values. Inferential statistics for demographics, perioperative characteristics, PROMs, and MCID were utilized to compare between groups and/or postoperative improvement. RESULTS: After matching, there were a total of 56 patients, with 30 patients with symptoms <1-year. The <1-year cohort reported significant improvement in all time points in VAS back/leg and 12-week/6-months in ODI. The >= 1-year cohort demonstrated significant improvement in 6-month Patient-Reported Outcomes Measurement - Information System Physical Function, 6-week to 1-year VAS back, 6-week VAS leg, and 6-month OW. The <1-year cohort had higher MCID attainment rates in 1-year VAS back/leg. CONCLUSIONS: Independent of symptom duration, patients reported significant improvement in back pain at all postoperative periods. Patients presenting with shorter symptom duration consistently reported significant improvement in leg pain postoperatively. Patients with shorter symptom duration demonstrated greater MCID achievement in back and leg pain. Patients indicated for outpatient MIS-TLIF may benefit more from earlier intervention following onset of symptoms.