Laurie Jean Mathiason "was essentially normal" before visiting a Saskatoon chiropractor on Feb. 3, neuropathologist Robert Macaulay testified Thursday.

The 20-year-old woman was rushed to hospital in a coma Feb. 4 after a neck adjustment by chiropractor Stacey Kramer. Mathiason subsequently died. Macaulay did the autopsy.

A chiropractic adjustment is a repositioning or correction of the vertebrae.

What likely happened was that the artery in Mathiason's neck was punctured during a neck adjustment on Feb. 3, Macaulay said.

But the next day, Mathiason returned to Kramer because her neck was still sore.

The adjustment dislodged a blood clot that likely formed the previous day, sending it up to the brain, Macaulay said.

The clot "plugged (the artery) like a cork," cutting off oxygen and blood flow to the base brain, he said. The area in question controlled her body's cardiorespiratory centres.

The inquiry has heard that Mathiason started to convulse, twitch and foam at the mouth after her last adjustment by Kramer.

She fell into a coma and doctors declared her brain dead the next day. They kept her body on life support for another two days to allow her kidney, liver and heart valves to be donated.

Kramer has testified the treatment she gave Mathiason the last day was more gentle than normal. Macaulay said the chances of Mathiason puncturing her artery just by turning her head were less than one per cent.

"This type of puncture is very rare. It was completely punctured."

A juror asked Macaulay if there should be more communication between the medical community and chiropractors.

"That question is a bit loaded. I'll take the bullets out one by one."

Macaulay said he wants evidence from chiropractors that what they do is a legitimate treatment for a clearly identified problem.

More information and evidence is needed about what exactly chiropractors do and why they do it before the two groups can talk, he said.

He was also asked about the risk of strokes from chiropractic treatments.

Macaulay said his research found there have been strokes after chiropractic treatments but it's not clear how many occurred and under what circumstances.

According to the Canadian Chiropractic Association, some patients have suffered strokes because of an adjustment, but noone has died.

The association says the incidence of stroke from an adjustment is about one in two million or three million procedures.

A fatality inquiry, like the one into Mathiason's death, is held to examine the circumstances of a death. It can recommend ways to avoid a similar incident but cannot assign blame.

Saskatoon Star Phoenix

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