Functional Outcomes In Musculoskeletal Oncology

Abstract

In musculoskeletal oncology, limb salvage surgery is now the standard of care for most patients with bone or soft tissue tumors of the extremities. There has been an increased interest in quantifying functional outcomes following limb salvage with both physician reported and patient reported outcome tools utilized. However, due to the rarity of the disease and lack of prospective data, there remains significant gaps in the literature surrounding functional outcomes in this population. This thesis proposes minimal important difference values for commonly used functional outcome measures and created a predictive model for postoperative function for musculoskeletal oncology patients following lower extremity limb salvage and endoprosthetic reconstruction.

The data for this thesis was retrieved from the Prophylactic Antibiotic Regimens in Tumor Surgery (PARITY) trial database and included patients undergoing lower extremity surgical resection and endoprosthetic reconstruction for bone or soft tissue tumors. Utilizing this data, we provided answers to two important clinical questions 1) establishing minimal important difference (MID) values for commonly utilized functional outcome scoring systems and 2) determine patient and tumor factors predictive of postoperative function.

We developed both anchor-based and distribution-based MID values for both the Musculoskeletal Tumor Society Score and the Toronto Extremity Salvage Score, the two most utilized functional outcome tools in the field. Secondly, we characterized the longitudinal changes in function following endoprosthetic reconstruction and identified patient and tumor predictors of postoperative function. On average, patient function improved significantly from their preoperative baseline to 1-year follow-up, exceeding the predefined MID values. Older age, poor preoperative function, and endoprosthetic reconstruction for soft tissue sarcomas were associated with worse outcomes; reconstruction for giant cell tumors were associated with better post-operative function.

Overall, these two studies aim to provide a deeper and more meaningful understanding of functional status in musculoskeletal oncology patients.