Knee megaprosthesis: Analysis of clinical outcomes, complications, and implant survival across complex indications

Knee megaprosthesis are an essential solution for managing complex pathologies, including peri-prosthetic fractures and tumor resections. However, their application is frequently associated with high rates of mechanical and infectious complications, necessitating thorough evaluation of functional outcomes and implant survival rates. This retrospective study included 28 patients who underwent knee megaprosthesis for complex fractures, pseudarthrosis or tumor-related indications. Functional outcomes were assessed using the Knee Society Score (KSS) and the Knee Society Functional Score (KSKF). Complications were classified according to Henderson's classification, and implant survival rates were calculated based on a mean follow-up of 3.7 years. The gross survival rate of the implants was 51.5 %, while the adjusted survival rate was 42.9 %. Infectious complications were observed in 17.8 % of cases, and mechanical failures occurred in 7.1 %. Postoperative functional scores demonstrated moderate improvement, although limitations remained common among patients who experienced complications. Knee megaprosthesis provide a viable solution for complex knee pathologies but carry a significant risk of complications. Rigorous patient selection, implant customization strategies, and optimized follow-up protocols are crucial to improving long-term outcomes.