Oncological and functional outcomes of pathological fractures of lower extremities in patients with malignant bone tumors

As managing pathological fractures of the extremities can be difficult, the present study aimed to present a treatment algorithm for lower extremity bone malignancies. A total of 38 patients with impending and pathological fractures were treated at the Department of Orthopedic Surgery in Kindai University Hospital. Age, sex, fracture site, type of primary malignancy, number of metastases, pre-fracture Eastern Cooperative Oncology Group performance status (ECOG-PS) score, adjuvant therapy, treatment modality, operative time, blood loss, postoperative complications, Musculoskeletal Tumor Society (MSTS) score, outcomes, follow-up period and the MSTS scores and ECOG-PS were compared in cases of primary malignant tumors and those cases of metastatic malignant tumors were retrospectively surveyed. Post-treatment MSTS scores in cases of impending and pathological fractures were compared between intramedullary nail fixation and non-intramedullary nail fixation procedures. Disease sites included the sub-trochanteric femur in 10 patients, trochanteric femur in 8, femoral diaphysis in 7, femoral neck in 5, bilateral trochanteric femur in 3, proximal tibia in 3 and distal femur in 2 patients. A total of 10 patients had metastases between 3-20 sites. The median pre-fracture ECOG-PS score was 1. Adjuvant radiotherapy was administered to 5, chemotherapy to 8 and radiotherapy with chemotherapy to 10 patients. Surgical procedures included intramedullary nails in 18 patients, tumor arthroplasty in 4, plate fixation in 3, artificial head replacement in three, compression hip screw (CHS) in 3, conservative treatment in 2, bilateral intramedullary nail fixation in 2 and artificial bone stem with combined intramedullary nail and plate fixation, right-sided artificial head replacement and left-sided CHS in 1 patient each. The MSTS score was 19.9 +/- 8.95 for intramedullary nail fixation and 24.3 +/- 7.45 for other procedures, with a negative association between the MSTS score and pre-fracture ECOG-PS. The median follow-up period was 8 months. The outcomes were as follows: Alive with disease, 23 patients; continued disease-free, 1 patient; and dead due to disease, 14 patients. The 1-year postoperative overall survival rate was 60.5%. Moreover, the group with metastatic malignant tumors, which had significantly worse ECOG-PS, had significantly lower MSTS scores than the group with primary malignant tumors. The authors' treatment algorithm for malignant bone tumors of the lower extremity was shown to be useful.