Stroke specialist testifies at inquest
By GAY ABBATE
Friday, May 17, 2002 Print Edition, Page A19
One of every 100,000 Canadians suffers a stroke each year as a result of neck manipulation, a coroner's inquest has heard.
The figure quoted by neurologist John Norris is in stark contrast to the one-in-a-million odds cited by the chiropractic profession.
Dr. Norris, who is a member of the Canadian Stroke Consortium, bases his numbers on studies by other scientists. The consortium is based at Sunnybrook Health Sciences Centre in Toronto.
He made his remarks at the inquest looking into a possible link between the stroke-related death of Lana Dale Lewis and chiropractic neck manipulation.
Although called by Tom Schneider, the coroner's counsel, Dr. Norris was expected to present data that supported the Lewis family's position that there is a link between strokes and neck adjustments by chiropractors, physiotherapists and physicians.
In a multimillion-dollar civil lawsuit, the family alleges that a neck adjustment killed the 45-year-old mother of three. She died on Sept. 12, 1996, 17 days after a Toronto chiropractor treated her for migraine headaches.
Much of the doctor's testimony yesterday tended to support the position of the chiropractic profession, which has argued during 18 days of hearings that the fatal stroke was caused by a clogged left vertebral artery inside the skull.
Dr. Norris told the inquest that about 90 per cent of the 75,000 strokes reported each year in Canada are caused by clogged arteries.
The Lewis family lawyer, Amani Oakley, has tried to show that the artery in the neck was stretched during chiropractic treatment. That stretching resulted in a blood clot that travelled up into the brain and caused the stroke.
At the heart of the debate over the cause of death is whether a dissection was present in the neck below the skull. A dissection is a tear in an artery wall.
Several experts have testified that neck manipulation was not a factor because a tear was not detected during the pathological examination after her death.
However, one neuropathologist who supported the Lewis family's theory on the cause of death testified that the tear was not visible because it had healed.
Dr. Norris said he would expect to see a dissection in the lower neck if the chiropractic manipulation had caused an injury.
He agreed with lawyer Tim Danson, who represents the Canadian Chiropractic Association and the Canadian Memorial Chiropractic College in Toronto, that Ms. Lewis's uncontrolled hypertension and her smoking put her at high risk of a stroke.
Dr. Norris said that simple, everyday movements, such as backing a vehicle out of a driveway or swinging a golf club, can cause dissections.