Study Design. Secondary analysis of prospective study. Objective. To analyze the impact of prior total knee arthroplasty (TKA), total hip arthroplasty (THA), or both on the Oswestry Disability Index (ODI) two years after elective lumbar surgery. Background. Degenerative conditions that cause pain and mobility loss significantly reduce quality of life. The rising prevalence of total joint arthroplasties (TJA) and spinal surgeries complicates treatment and may result in persistent postoperative symptoms. Understanding how these surgeries interact and how surgical history and underlying conditions influence postoperative outcomes is crucial. Methods. A secondary analysis was performed on a prospective study of patients undergoing lumbar surgery for degenerative conditions. Patients with a two-year ODI follow-up were included. ODI was prospectively assessed pre- and postoperatively. Patients without ODI-assessment were excluded. Differences in pre- and postoperative ODI were evaluated, and patients were categorized based on ODI-improvement. Statistical analyses included Mann-Whitney-U-test, univariable logistic regression, and multivariable logistic regression adjusted for age, sex, and BMI. Results. Overall, 385 patients (57% female, 65±10 y) were included. 46 patients (12%) had prior THA, 34 (9%) patients had prior TKA, and 11 (3%) patients had both. ODI-improvement was achieved in 91%. After adjusting for covariates, combined TKA and THA was significantly associated with postoperative ODI non-improvement (OR9.96, 95%CI 2.53-38.3, P =0.001). Prior TKA also tended to be a risk factor for ODI non-improvement, although not statistically significant ( P =0.052) after adjusting for covariates. Conclusion. Patients with prior concomitant TKA and THA have higher odds of ODI non-improvement two years postoperatively, suggesting that concurrent musculoskeletal degeneration of the spine and lower extremities may negatively impact improvement after lumbar surgery. These results highlight the connection not only between the hip but also the knee and spine.

The Impact of Prior Hip or Knee Arthroplasty on Oswestry Disability Index Two Years after Elective Lumbar Surgery