The Effect of Whole Body Vibration in Individuals With Parkinson's Disease

Previous studies reported that whole body vibration has the potential impact on balance and walking abilities in individuals with Parkinson's disease; however, the inconsistent treatment protocols and different experimental designs lead to inconclusive results. Therefore, the purpose of this study is to investigate the short term and long term effect of whole body vibration on sensorimotor function in individuals with Parkinson's disease. The experimental design will be randomized double-blinded controlled trial. Sixty individuals with idiopathic Parkinson's disease will be randomly assigned to two groups and they are non-random whole body vibration group and conventional therapy group. Each participant will receive the treatment about one hour after the administration of medicine. For non-random whole body vibration group, participants will be required to maintain the erect standing position on the vibratory platform and the frequency and amplitude of vibratory stimuli will be 6Hz and 3mm respectively. Each treatment includes five sessions and each session is composed of one minute whole body vibration and one minute rest. For the conventional therapy group, participants will receive the occupational therapy including dynamic balance training and functional ambulatory training. Each session is 10 minutes in both groups and all participants will receive one and twelve treatment sessions for short-term and long-term effect respectively. Outcome measures include proprioceptive sensitivity threshold of upper limb, position sense test of the knee joint, Unified Parkinson's disease rating scale-motor (UPDRS motor), functional reach, and time up and go test (TUG). Specifically, the investigators want to answer the following four questions: 1) Is there any difference in proprioceptive sensitivity, motor performance and balance before and after treatment in individuals with Parkinson's disease? 2) Is there any difference in short-term and long term effect of whole body vibration in individuals with Parkinson's disease? 3) Is there any difference in treatment effect in individuals with Parkinson's disease in Taiwan?

Each participant will receive the non-random type whole body vibration treatment about one hour after the administration of medicine.

For the conventional therapy group, participants will receive the occupational therapy including dynamic balance training and functional ambulatory training. Each session is 10 minutes.

Each participant will receive the treatment about one hour after the administration of medicine. For non-random whole body vibration group, participants will be required to maintain the erect standing position on the vibratory platform and the frequency and amplitude of vibratory stimuli will be 6Hz and 3mm respectively. Each treatment includes five sessions and each session is composed of one minute whole body vibration and one minute rest.

Participants will receive the occupational therapy including dynamic balance training and functional ambulatory training.

This experiment will use psychophysical methods to assess subject perception, the psychophysical methods developed two thresholds: detection threshold/absolute threshold and difference threshold/just noticeable difference threshold (JNDT). Difference threshold represents the minimum difference between two different intensity stimulation. In this experiment, the investigator will test the difference threshold for position sense and passive motion sense

In the beginning, each subject sits comfortably in an arm chair (knee flexion 90o). The subject's non-affected leg is passively moved at three target angles (knee flexion 15, 30 and 70 degrees), and maintained the testing angle for 15 seconds before being return to knee flexion 90 degree (initial position). Subjects will be required to move the knee joint of the ipsilateral leg to the target angle. The assessor will use a hand-held goniometer to measure the angle of knee flexion. Each target angle will be measured three times, and both knee joints will be tested.

Unified Parkinson's disease rating scale is used to evaluate the disease progression for Parkinson's disease (PD). Higher scores represent the more advanced disease progression. It includes four subscales: mentation, behavior and mood, activities of daily living, motor examination, and complications of therapy. In this study, the investigator mainly use the motor examination subscale. There are 14 items in motor examination including speech, facial expression, tremor at test, action or postural tremor of hands, rigidity, finger taps, postural stability, gait, body bradykinesia and hypokinesia…etc. The purpose is to evaluate the motor performance for individuals with PD (Movement Disorder Society Task Force on Rating Scales for Parkinson's, 2003).

The purpose of functional reach test is used to measure balance function. Participants can be in standing or sitting position (unable to stand). It measures the difference of distance in centimeters between arm's length with arms at 90° flexion and maximal forward reach with a fixed base of support.

The purpose of time up and go test (TUG) is to evaluate the mobility function including both static and dynamic balance. The experimenter uses a stopwatch to measure the time that a person takes to rise from a chair, walk three meters, turn around, walk back to the chair, and sit down. Participants can walk independently or with walking devices. It is easy to administer and can applied to elderly population.

Inclusion Criteria: agree to sign the informed consent form. diagnosed with idiopathic Parkinson's disease with Hoehn and Yahr stage 2~3 cognitive impairment (Mini-Mental State Examination [MMSE] score greater than 24 points no depression as evaluated by the Beck Depression Inventory no severe arm injuries or shoulder dislocation which might interfere with proprioceptive function can perform reaching movement no diagnosed peripheral nerve disorders or other neurologic conditions no severe tremor which might interfere with the measurement proprioceptive function Exclusion Criteria: diagnosed with other central nervous system diseases, ex: stroke had surgeries in head or arms unable to sit for assessment