Relationship between gastrocnemius and soleus muscle thickness assessed by ultrasound and balance and fear of falling in hemiplegic patients

Structural and functional changes occurring in the lower extremity muscles of hemiplegic stroke patients play a decisive role in gait ability, balance impairment, and fall risk. In this context, the relationship between muscle architecture parameters such as the thickness of the gastrocnemius and soleus muscles and functional performance is being investigated. Ultrasonography is a reliable and accessible method for the non-invasive assessment of muscle thickness. Yakut et al. (2024) reported that in acute stroke patients, particularly the thickness and cross-sectional area of the soleus muscle were significantly associated with the Berg Balance Scale, Single-Leg Stance Test, and Timed Up and Go Test. In the same study, it was also shown that the thickness of the gastrocnemius muscle on the non-paretic side was related to balance. Onat et al. (2022) demonstrated correlations between lower extremity muscle architecture and measures such as the Timed Up and Go Test, Fugl-Meyer Lower Extremity Assessment, and Functional Independence Measure, emphasizing that the gastrocnemius and soleus muscles play a determining role in motor and functional level. Suh et al. (2022) reported that trunk muscle thickness was significantly associated with the Berg Balance Scale, Functional Ambulation Scale, and Functional Reach Test. In this study, gastrocnemius and soleus muscle thickness will be evaluated using ultrasonography in subacute and chronic stroke patients, and their relationship with balance (Berg Balance Scale), mobility (Timed Up and Go Test and Functional Ambulation Scale), and fear of falling (Falls Efficacy Scale International) will be investigated. The study aims to provide original contributions to the literature by revealing the interaction between muscle architecture and both physical and psychosocial outcomes, and to support the development of targeted rehabilitation strategies for individuals at high risk of falling.