Myotonometry in Patients with Parkinson's Disease: Assessment of Pre and Post Treatment through Comparisons with Healthy Controls

The study aims to assess the myotonometer parameters of major pectoralis, biceps brachialis, femoral biceps and anterior tibialis in patients with Parkinson's disease before and after medical treatment using comparisons with healthy controls. A total of 49 patients with Parkinson's disease (69.76 +/- 6.39 years) and 42 healthy controls (60.48 +/- 7.62 years) were tested using MyotonPRO before and one hour after drug administration. Five parameters were recorded (frequency [Hz], stiffness [N/m], decrement, relaxation [ms] and creep). At pre-treatment assessment, significantly increased values of myotonometer parameters were recorded for major pectoralis and biceps brachialis, with the exception of decrement. Frequency and decrement were significantly higher in patients' femoral biceps and anterior tibialis. For all assessed muscles, frequency was significantly higher in Parkinson's disease patients one hour after medication intake. Stiffness, relaxation and creep had increased values in major pectoralis. For the lower limb muscles, decrement had greater values. We concluded that there were no significant differences of major pectoralis and biceps brachialis elasticity between patients with Parkinson's disease and healthy controls pre and post drug administration, with improved viscoelastic properties of biceps brachialis after medication. After drug administration, no significant differences of femoral biceps and anterior tibialis stiffness were noted between patients and controls.