Parkinson's Essay on the Shaking Palsy

Parkinson opened his essay with a one-sentence definition. The shaking palsy, or paralysis agitans, was involuntary trembling with lessened muscular power in parts at rest, even when supported, together with a tendency to bend the trunk forward and to pass from a walking to a running pace. The senses and intellect were unharmed. The disease, he wrote in the preface, had not yet found a place in the classification of nosologists.

He was a member of the Royal College of Surgeons, born in 1755 in Hoxton, in the East End of London, the son of a surgeon-apothecary. He had served six years as his father's apprentice and in 1785 attended John Hunter's lectures. He also collected fossils and wrote a standard textbook of paleontology.

The evidence was six men. One, a gardener of just over 50, had first noticed trembling in his left hand. Two were seen by chance in the street: a man of 62 who had worked as an attendant at a magistrate's office and had been ill for eight or ten years, and a man of about 65, of remarkably athletic build, who could no longer walk. A fourth came to Parkinson about an abscess, a fifth was seen only at a distance, and the sixth, aged 72, gave a full history.

Parkinson admitted he had no autopsy findings and that analogy stood in for anatomy. He placed the disease in the spinal cord within the upper cervical vertebrae, spreading as it progressed to the medulla oblongata. For treatment he suggested taking blood from the upper neck, then blisters and a kept-open discharge at the same spot. He published, he said, because the ideas might help if tried early, and he hoped others would take up the study.

Later in the century the Paris neurologist Jean-Martin Charcot proposed the name maladie de Parkinson. Charcot also corrected parts of the description, noting that the patients were slow and rigid, not weak.