Sarcopenia: definition, radiological diagnosis and clinical significance

Sarcopenia, defined as the progressive loss of skeletal muscle mass, strength and physical performance, is an increasingly relevant clinical condition due to its strong association with heightened morbidity, disability and healthcare burden. This review summarizes the evolution of sarcopenia’s definition, most recently updated by the European Working Group on Sarcopenia in Older People (EWGSOP) and emphasizes the critical role of radiological imaging in its diagnosis and monitoring. Particular attention is given to patients with osteoporotic vertebral compression fractures (OVCFs), a particularly vulnerable population in which sarcopenia is associated with poorer functional recovery, higher complication rates and increased risk of refracture following vertebral augmentation procedures such as percutaneous vertebroplasty (PVP) and kyphoplasty (PKP). A comprehensive narrative review of the literature up to June 2025 was conducted, focusing on studies, evaluating sarcopenia in OVCF patients treated with PVP or PKP, with particular attention to diagnostic imaging modalities (CT, MRI, DXA, and bioelectrical impedance analysis), anatomical landmarks (e.g., T12), muscle indices (skeletal muscle index, psoas muscle index, psoas-to-lumbar vertebral index, appendicular muscle index), and functional parameters (handgrip strength, gait speed). Radiological techniques each present specific advantages and limitations: DXA is widely available and validated but limited in assessing muscle quality; CT allows opportunistic screening and precise tissue analysis, increasingly enhanced by artificial intelligence for automated muscle segmentation and risk stratification; MRI provides high-resolution characterization of muscle composition without ionizing radiation although standardization and cost remain limiting factors; and ultrasound, while promising due to its portability and low cost, is still limited by operator dependence and lack of standardized protocols. Across studies on vertebral augmentation, sarcopenia definitions were inconsistent, limiting data comparability and clinical utility. A standardized diagnostic approach is therefore recommended, integrating low muscle mass measured by CT at the T12 level (e.g., skeletal muscle index), reduced muscle strength (e.g., handgrip), and impaired physical performance (e.g., gait speed).Sarcopenic patients undergoing PVP or PKP may benefit from multidisciplinary management strategies including nutritional support, resistance and balance training, and comorbidities, in order to reduce refracture risk and improve recovery. Establishing unified diagnostic criteria and leveraging radiological imaging and AI will be critical to improve early detection, guide treatment decisions, and improving clinical outcomes in this high-risk population. Implementing a shared and standardized assessment of sarcopenia in vertebral fracture patients holds significant potential to optimize preoperative planning, postoperative care, and long-term management.