Robert Poirier MD CCFP

Substantia nigra: the black substance, seat of movement and reward. Before becoming a physician, Dr Poirier conducted neurophysiological research in Parkinson disease, attempting to discover the perfect media to preserve human fetal ventral mesencephalic tissue. These dopaminergic neurons needed a substance they could sit in and live before transplantation into a person.

Part of his master’s-level research was acknowledgment of the suffering of human subjects, and Dr Poirier met them in transition: before they were to undergo a surgical procedure. Yet he too was also becoming something else.

The scientist in the OR: watching the patient prepped, draped, bur hole drilled, needle injecting fetal tissue slowly, in drops, a stereotactic field. He stood with other students, wondering about neurosurgery’s necromancy: the creation of a hole leading to intellect and abandon.

He entered medical school and was instructed in the classic neurological exam. His master’s degree required an awareness of the physical findings of Parkinson disease, though without clinical exposure there was then no opportunity (or need) to develop an understanding of what these things meant to the body. You can learn a thing but not know a thing until you feel a thing. Dr Poirier was therefore motivated to elicit in a wrist what he’d only known heretofore as a beautiful word, cogwheeling; to see stooped postures, flexed hips, shuffling gait, rigidity.

Dr Poirier has been practising for over a decade. One of his patients, a diabetic man in his seventies, slowly developed a telltale stoop over the course of years. His affect flattened, his face became a mask, his gait a slight shuffle. These signs were subtle and the man has preferred to focus instead on a stable diet-controlled diabetes. Dr Poirier hadn’t mentioned his mild suspicion of Parkinson disease because the patient suffered no decrease in function; but on this day the man complained of a tremor. The seat of movement, pointing to change.

The patient’s arms in hand, cogwheeling.

A permanent, decaying stage. Moving from the brief substance of disbelief, the man accepts Dr Poirier’s diagnosis and decides to conduct his own research into what can be done. Certain details of the man’s life have retreated, can come to mind no more, but Dr Poirier remembers: cogwheeling more prominent on the left than on the right.

• Copyright© the College of Family Physicians of Canada