ABSTRACT
James Parkinson’s classic 1817 monograph, An Essay on the Shaking Palsy, marks the first detailed account of the disease that now bears his name.1 This work was remarkable, because it was based solely on clinical interviews with three patients and street observations of three others, and his description of a clinical syndrome characterized by tremor, apparent weakness (due to a combination of bradykinesia and rigidity), and an abnormal gait remains unrivaled in its clarity and accuracy. Although our understanding of Parkinson’s disease (PD) and its many variants has grown immensely since that time, no proven diagnostic procedures or laboratory tests for the diagnosis of PD have emerged, and the diagnosis of PD is still based on the clinical interpretation of signs and symptoms, obtained through a detailed history and thorough neurologic examination. If and when neuroprotection moves from optimistic concept to therapeutic reality and is shown to prevent vulnerable neurons from degenerating, an early diagnosis of PD will be essential for initiating such life-saving treatment. Accuracy of diagnosis depends on a clear understanding of the varied clinical manifestations of PD, particularly the classical features that James Parkinson recorded in such lucid detail almost 200 years ago. Although it will be difficult for us to surpass his careful description, we have the advantage of time and a cumulative body of knowledge about the underlying pathophysiology of PD that Parkinson could only speculate about.
