Ab&&-We propose a new kinematic analysis procedure using triaxial accelerometers mounted to the wrist in the assessment of bradykinesia in patients with Parkinson's disease (PD). The deviation of the magnitude of the accelerometer vector signal from the magnitude of the gravitational acceleration is taken as a measure for effective magnitude of the acceleration at the position of the triaxial accelerometer. For low acceleration, two of the three angles describing the orientation of the lower arm can be derived from the accelerometer signals.