J. Clay Thompson

John Clay Thompson came to chiropractic as a career-changer and a technician. Raised in modest circumstances, he gained early mechanical experience in a machine shop and later worked in industry, until a serious illness changed his life: by his own account he was considered beyond help, yet experienced a full recovery under chiropractic care. That experience led him, in 1945 at the age of thirty-six, to the Palmer School of Chiropractic.

As a chiropractor, Thompson combined his grasp of mechanics and Newtonian physics with hands-on practice. He was troubled that the established adjusting techniques were tiring and uncomfortable for practitioner and patient alike. Around 1952 he developed a headpiece that "drops" slightly at the moment of the thrust — the Palmer-Thompson drop headpiece — for which he was granted a rare process patent in 1955. With B.J. Palmer's encouragement, this gave rise in 1957 to the full drop table with individually releasable segments.

The "segmental drop" principle uses the table's own movement to achieve a precise adjustment with considerably less force — gentler for patient and practitioner. Also characteristic of the Thompson Technique is its leg-length analysis for determining where adjustment is needed. Thompson taught for decades on the Palmer faculty (1947–1961, ten of them as head of research) and lectured on several continents; he received 23 patents on chiropractic equipment in all. His drop tables — still built today as the "Zenith Thompson" — shape practice worldwide, and the Thompson Technique is among the most widely used methods in the profession.