Comparison of rectus femoris muscle shear wave elastography and thickness on evaluation of frailty

The objective of this study is to evaluate the potential of rectus femoris shear wave elastography (RF-SWE) in assessing its impact on frailty and physical performance parameters, using a comparative analysis with rectus femoris muscle thickness (RF-MT). A total of 149 participants aged 60 and above were included in this research. All participants underwent a comprehensive geriatric assessment, frailty status assessment (using the frailty phenotype [FFP]), and evaluation of physical performance parameters (utilizing the short physical performance battery score [SPPB] and handgrip strength measurement). RF-MT and RF-SWE were measured by a radiologist with participants in a prone and relaxed position. The mean age of participants was 73.8 ± 6.5, with 61.7% (n = 92) being female. Participants were divided into 2 groups based on their frailty status, with 40 (26.8%) identified as frail and 109 (73.2%) as non-frail. RF-MT exhibited a significant correlation with frailty and the SPPB, while RF-SWE did not exhibit significant associations except for handgrip strength. In regression analyses, RF-MT was found to be significantly and independently associated with physical frailty. The optimal cutoff value for RF-MT was determined to be ≤ 17.74 (area under the ROC curve [AUC], 0.752; 95% CI 0.675-0.819; p