Shear wave elastography, as a feasible tool, can be used to reflect the lower limb dysfunction in patients with...

To explore the additional value of shear wave elastography (SWE) in chronic obstructive pulmonary disease (COPD) patients. Ultrasound elastography of the rectus femoris and patellar tendon was performed to determine the mean elasticity index (SWE_mean) of the rectus femoris (SWE_RF) and patellar tendon (SWE_PT) in 56 patients with COPD and 53 healthy controls. Clinical tests included the COPD Assessment Test (CAT), the dyspnea index score (modified British Medical Research Council (mMRC)score), the Five-Repetition Sit-to-Stand Test(5STS) and the Six-Minute Walk Test (6MWT). We compared differences in SWEmean between healthy controls and COPD patients while describing the correlation between SWEmean and clinical tests in COPD patients. Both the intra-observer and inter-observer repeatability of SWE performance were excellent (all correlation coefficients > 0.75; p < 0.05). There was a statistically significant difference between healthy controls and COPD patients in the SWE_RF and SWE_PT between healthy controls and COPD patients (p < 0.001). The COPD patients had smaller SWE_RF and larger SWE_PT than healthy controls. The SWE_RF was positively correlated with the 6MWT (r = 0.591, p < 0.001), and negatively related to the mMRC (r = - 0.794, p < 0.001), CAT (r = - 0.894, p < 0.001) and 5STS (r = - 0.928, p < 0.001). But the SWE_PT was positively related to the 6MWT (r = 0.269, p < 0.05), mMRC (r = 0.398, p < 0.05), CAT (r = 0.377, p < 0.05) and 5STS (r = 0.332, p < 0.05). SWEmean of COPD patients was statisticant, different from that of healthy controls, and associated with clinical tests. SWE was a simple and feasible tool for reflecting the lower limb dysfunction in patients with COPD.