Muscle thickness and functional performance of patients with Parkinson’s disease

Abstract The aims of this study were: a) to check if there is difference between muscle thickness measured by ultrasonography at three different sites, elbow flexors and knee extensors of patients with Parkinson's disease (PD); b) to check if there is correlation between muscle thickness and functional performance in patients with PD. Muscle thickness was assessed by ultrasonography at three anatomical sites in elbow flexors (proximal - EF1, medial, EF2, and distal - EF3) and knee extensors (proximal - EK1, medial - EK2, and distal - EK3), as well as functional performance assessment (chair stand and arm curl) of 31 patients with PD. The results suggest that EF3 muscle thickness was significantly (p> 0.05) lower than EF2 and EF1. Muscle thickness of knee extensors was statistically different in the anatomical points of rectus muscles and vastus medialis muscles (EK1>EK2>EK3). There was no correlation between muscle thickness and functional performance of lower (r= 0.17; p= 0.35) and upper limbs (r= -0.17; p= 0.34) of PD patients. The results indicate that the anatomical point has significant influence on the muscle thickness of elbow flexors and knee extensors of patients with PD. Thus, the careful determination of the evaluation of muscle thickness sites is a key variable when the goal is to quantify muscle thickness in patients with PD.