Osteoarticular infections represent a major therapeutic challenge and are associated with high morbidity, multiple surgical interventions, prolonged antibiotic therapy, and functional impairment. They may trigger a systemic inflammatory response and a hypercatabolic state, leading to reduced appetite, increased muscle proteolysis, loss of lean body mass, and weight loss. Following surgical control of the infection, a reduction in the inflammatory and hypercatabolic state is expected, with subsequent metabolic, functional, and nutritional recovery. In this context, weight recovery may represent a simple and objective marker of systemic recovery, although its prognostic potential remains largely unexplored.