We aimed to examine the predictability of the need for soft tissue reconstruction during limb-sparing surgery through preoperative magnetic resonance (MR) imaging in patients diagnosed with a malignant bone tumor in the distal femur. The study included 42 patients who were operated for a bone sarcoma of the distal femur at our clinic between 2016 and 2018. The recorded parameters included the demographic characteristics of the patients, tumor diagnosis, tumor side, total tumor volume, tumor soft tissue component volume, tumor soft tissue component volume-to-total tumor volume ratio, tumor localization by MR imaging, the need for soft tissue reconstruction, the muscles used for soft tissue reconstruction, the biopsy site, and the biopsy type. Tumor volume was calculated on MR imaging of