Imaging-Based Markers of Sarcopenia in Lower Limb Ischemia: A Systematic Review

Background/Objectives: Imaging-based markers of sarcopenia have emerged as potential indicators of frailty and predictors of clinical outcomes in patients with lower limb ischemia undergoing revascularization. However, the available evidence remains inconclusive. This systematic review aims to provide a comprehensive overview of current imaging-based approaches to sarcopenia assessment and to evaluate their relationship with clinical outcomes in this population. Methods: This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines and prospectively registered in the International Prospective Register of Systematic Reviews (PROSPERO) database: ID CRD420251229527. A literature search was performed in PubMed and Scopus to identify studies published between 1 January 2020 and 1 August 2025. Studies assessing imaging-derived markers of sarcopenia in adults undergoing revascularization for lower limb ischemia were included. Due to heterogeneity in imaging methods, sarcopenia definitions and reported outcomes, a narrative synthesis was performed. Results: Nine studies involving 2563 patients were included in this review. Computed tomography (CT) was the predominant imaging modality used for sarcopenia assessment, with muscle measurements most frequently obtained at the level of the third lumbar vertebra (L3). Commonly reported imaging-derived markers included the skeletal muscle index, psoas muscle-based parameters and muscle radiodensity. Assessment strategies varied across studies, particularly with respect to measurement techniques, anatomical landmarks and the thresholds used to define sarcopenia. Most studies reported an association between imaging-derived low muscle mass and increased long-term mortality; however, independent associations after multivariable adjustment were less consistent. Findings regarding postoperative complications and limb-related outcomes were limited and inconsistent. Conclusions: Current evidence suggests that imaging-derived muscle markers may provide additional prognostic information regarding long-term mortality in patients undergoing revascularization for lower limb ischemia, while associations with postoperative complications and limb-related outcomes remain inconsistent. However, the small number of retrospective studies and substantial methodological heterogeneity limit their comparability, highlighting the need for standardization in future research.