ABSTRACT
Dating back to 1817 and his first descriptions of six patients with the “shaking
palsy,” James Parkinson established the common motor symptoms of parkinson-
ism consisting of resting tremor, decreased motor control, stooped posture, and
gait abnormalities (1). Today, clinicians still diagnose idiopathic Parkinson’s
disease (PD) based on the presence of four cardinal motor features: bradykinesia,
tremor, rigidity, and postural instability (U.K. Parkinson’s Disease Society Brain
Bank Clinical Diagnostic Criteria) (2). Bradykinesia and one other symptom
listed are considered sufficient to make a diagnosis of probable PD.
