Changes in Muscle Thickness and Echo Intensity in Chronic Stroke Survivors: A 2-Year Longitudinal Study

BACKGROUND AND PURPOSE: The objective of this study was to identify 2-year longitudinal changes in the muscle thickness (MT) and echo intensity (EI) of the abdominal, thigh, and lower limb muscles in chronic stroke survivors. METHODS: This study included 15 chronic stroke survivors aged 74.1±9.9 years. The MT, EI, and subcutaneous fat thickness values of the following muscles on the paretic and nonparetic sides were assessed on transverse ultrasound images: rectus abdominis, external oblique, internal oblique, transversus abdominis, rectus femoris (RF), vastus intermedius, vastus lateralis (VL), vastus medialis, tibialis anterior, gastrocnemius, and soleus. The ultrasound measurements were performed both at baseline and 2 years later. RESULTS: After 2 years, the VL on the paretic side showed a significant decrease in MT (p=0.031) and increase in EI (p=0.002), whereas the RF on the nonparetic side showed a significant decrease in EI (p=0.046). Correlation coefficient analyses showed that changes in MT (r=0.668, p=0.012) and EI (r=0.597, p=0.018) of the VL on the paretic side were significantly associated with a change in the body mass index. CONCLUSIONS: The findings of this longitudinal study suggest that the VL on the paretic side is subject to deteriorations in muscle quantity and quality, and conversely that the RF on the nonparetic side shows an improvement in muscle quality after 2 years in chronic stroke survivors.