Osteosarcopenia in hip fracture: taking cues from pathophysiology for clinical practice

Hip fractures are common in older and frail adults, and the risk of adverse outcomes and mortality is significantly increased in patients affected by osteosarcopenia. Identifying particularly vulnerable subjects is a critical step to act aimed at promoting postoperative recovery and reducing the risk of adverse events. However, the diagnostic criteria that are currently used to establish the severity of osteosarcopenia are not easily applicable in patients with hip fractures and impaired mobility. In this review, the new knowledge on the pathophysiology of osteosarcopenia that provides several cues for studying biomarkers potentially useful in clinical practice is summarized. Although significant progress has been obtained in understanding the biological mechanisms leading to the involution of the bone- muscle unit, further studies are needed to identify clinically relevant biomarkers and their diagnostic accuracy in establishing the severity of the osteosarcopenia, predicting adverse outcomes, and guiding physicians in choosing appropriate therapeutic interventions.