Idiopathic Parkinson's Disease - Are You Checking for Postural Instability?

If this is idiopathic Parkinson's disease, it really should start asymmetrically. If somebody has very symmetric symptoms, that would make you wonder whether or not they have a different flavor of Parkinsonism. How do you assess for postural instability on physical examination? So the test that you're describing is a pull test and you are checking for retropulsion.