Parkinson disease

Definition

• Degenerative neurological disorder characterized by progressive bradykinesia, rest tremor, rigidity, and postural instability

Pathophysiology

• Destruction of substantia nigra

Differential Diagnosis

• See Parkinson syndrome

Clinical Presentation

• Rest tremor at 4-6 Hz, inhibited by movement and sleep, worsened by stress
  • Pill-rolling
• Rigidity, with increased tone and cog-wheeling
  • No spasticity
  • Often worse with repeated flexion
• Bradykinesia
  • Short, shuffling gait with festination
  • Loss of arm swing
  • Micrographia
• Postural hypotension
• Glabellar tap reflex, normally stops after 5-10 taps

JAMA Rational Clinical Exam

• Change in speech (LR+ 2.6, LR- 0.73)
• ...