Outcomes of transforaminal lumbar interbody fusion in a working-age population (≤50 years): a propensity score–matched cohort study

BACKGROUND: Prior studies of transforaminal lumbar interbody fusion (TLIF) have primarily focused on older populations, with limited evaluation of younger adults as a distinct cohort. Whether presumed biologic advantages in younger patients translate into superior long-term outcomes remains unclear. This study aimed to assess whether younger age (≤50 years) is associated with improved clinical, radiographic, and patient-reported outcomes following TLIF. METHODS: Adults undergoing TLIF for degenerative lumbar pathology at a single center (2018-2022) with ≥2-year follow-up were retrospectively analyzed. Patients were stratified by age (≤50 vs >50 years). A 1:2 propensity score match was performed using sex, BMI, age-independent comorbidity index, prior fusion, and number of levels fused. Outcomes included complications, reoperation, radiographic parameters, and patient-reported outcomes (ODI, VAS back/leg pain). Univariate and multivariable analyses adjusted for covariates. RESULTS: From 854 patients, propensity matching yielded 89 aged ≤50 years and 178 aged >50 years. Complication rates were comparable between groups (reoperation: 19.1% vs 22.5%, p = 0.53; pseudarthrosis: 3.4% vs 5.6%, p = 0.42; subsidence: 12.4% vs 19.1%, p = 0.17; ASD: 10.1% vs 15.7%, p = 0.21). On multivariable analysis, age >50 was not associated with reoperation, pseudarthrosis, or subsidence, but independently predicted adjacent segment disease (OR 2.08, 95% CI 1.02-4.66; p = 0.044). Radiographic outcomes were comparable. Older age was independently associated with greater 2-year improvement in ODI, VAS back, and leg pain (all p < 0.05). CONCLUSIONS: Younger age was not associated with reduced complications, reoperation, or radiographic failure after TLIF. Older patients demonstrated greater patient-reported improvement despite similar surgical outcomes. This suggests that age alone should not be considered a predictor of superior TLIF outcomes and highlights the importance of individualized patient counseling regarding expected functional benefit.