Long-term outcomes after knee endoprosthesis for a rare HIV-associated proximal tibial osteosarcoma: 15-year follow-up.

Primary bone malignancies such as osteosarcoma are exceedingly rare in HIV-positive individuals, presenting unique surgical and long-term management challenges. The aim of this case report is to evaluate the 15-year clinical and functional durability of limb-salvage surgery in an immunocompromised patient. A 29-year-old HIV-infected female presented with a proximal tibial mesenchymal tumor. She underwent surgical resection followed by endoprosthetic reconstruction. During the follow-up period, the patient received regular antiretroviral therapy to manage her HIV infection. At 15 years post-surgery, radiographic assessment confirmed sustained implant stability, with no evidence of aseptic loosening, infection, or structural failure. Clinical evaluation demonstrated excellent functional recovery, with a symmetric gait and no need for additional surgical interventions. Notably, HIV markers were undetectable, further highlighting the successful management of both the tumor and the patient's HIV infection over the long term. This case demonstrates the long-term feasibility of successful limb-salvage surgery in HIV-positive patients, emphasizing the importance of multidisciplinary care and effective HIV management for sustained functional outcomes.