A case of an 18-year-old female with a gradually enlarging thigh mass for two years. She was referred to our institution for further evaluation and management, and a needle biopsy was done. The histopathology report revealed atypical spindle cell proliferation, and immunostaining was unremarkable. The multidisciplinary team suggested surgery and because of financial constraints for tumor prosthesis, an extra-articular resection, and a knee fusion using a long intramedullary rod with a non-vascularized fibular graft.  The final histopathology report revealed low-grade central osteosarcoma.