Measuring the maximum pinching force is a good procedure to evaluate bradykinesia in patients with Parkinson's disease

We assessed motor disability and disease severity by measuring the maximum pinching force for 1 minute in patients with Parkinson's disease (n=36) and age-matched normal controls (n=38). Decrement of muscle force during 1 minute did significantly differ between two groups. The incline of force/time curve at the onset of movement significantly correlated with motor scores related to bradykinesia in UPDRS-motor and disease severity in male PD patients, while female PD patients showed that pinching muscle forces at the middle or end point significantly correlated with disease severity and scores related to motor disability. We propose that measuring the maximum pinching force is a good procedure to evaluate motor disability, especially bradykinesia, in PD patients.