The Validity of Muscle Ultrasound in the Diagnostic Workup of Sarcopenia Among Older Adults: A Scoping Review

Jessica S Staempfli,1 Melanie Kistler-Fischbacher,2 Jan Gewiess,3 Johannes Dominik Bastian,3 Anna K Eggimann4 1Medical Faculty, University of Bern, Bern, Switzerland; 2Centre on Aging and Mobility, Department of Geriatrics and Aging Research, University of Zurich, Zurich, Switzerland; 3Department of Orthopaedic Surgery and Traumatology, Inselspital, Bern University Hospital, University of Bern, Bern, 3010, Switzerland; 4Department of Geriatrics, Inselspital, Bern University Hospital, and University of Bern, Bern, 3010, SwitzerlandCorrespondence: Anna K Eggimann, Department of Geriatrics, Inselspital, Bern University Hospital University of Bern, Freiburgstrasse 40, Bern, CH-3010, Switzerland, Tel +41 31 632 54 89, Email anna.eggimann@insel.chPurpose: Muscle ultrasound has emerged as a promising method in the diagnostic work-up of sarcopenia. The objective of this scoping review was to explore the validity of muscle ultrasound against the latest sarcopenia definitions among older adults.Methods: We adhered to the PRISMA guidelines for scoping reviews. A systematic search of databases was performed by two independent reviewers. All articles comparing the performance of ultrasound to an internationally acknowledged sarcopenia definition among older adults (≥ 60 years) and published between 2019/01/01 (the year updated sarcopenia definitions were introduced) and 2023/11/15 were included. Data were extracted and collated by muscle and muscle parameters.Results: Out of 2290 articles screened, six studies comprising 24 validity tests among a total of 1619 older adults (mean age 74.1 years, 52.2% female) were included. The validity tests investigated the rectus femoris (n = 7), biceps brachii (n = 5), gastrocnemius medialis (n = 4), tibialis anterior (n = 4), soleus (n = 3), and rectus abdominis (n = 1). The parameter muscle thickness (MT) (n = 14) was most commonly measured. The latest European and Asian sarcopenia definitions (EWGSOP2, AWGS2) were applied as reference standards in four validity tests each. None of ...