A controversial foot doctor is now facing accusations about the use of questionable implants on patients without their knowledge.

Go Public and Radio-Canada recently reported how, after being banned from dentistry in Quebec following serious problems with patients, Pierre Dupont reinvented himself as a foot specialist in Ontario. One of his Ottawa patients contacted us after having trouble healing from foot surgery done by Dupont.

Our investigation has now found Dupont's patients paid him thousands of dollars for a procedure that uses a Health Canada approved HyProCure stent, but may have instead received fake implants.

HyProCure is a small titanium stent that's inserted into the foot of those with flat feet. It was approved by Health Canada in 2006 after more than a decade of development and regulatory approvals.

Pierre Dupont has been banned from using stents on his patients by the College of Chiropodists of Ontario. (Ottawa Foot Practice )

The inventor of the HyProCure stent, Dr. Michael Graham, told Go Public he was contacted by several of Dupont's patients and former colleagues who told him they suspected the Ottawa foot doctor was selling HyProCure to some patients, but giving them his own 'knock-off' implants instead.

"I was absolutely floored ... I had no idea he was making these knock-offs," says the founder of U.S.-based GraMedica.

He's a bad apple and needs to be stopped. - Michael Graham, HyProCure inventor

"He's basically out there using a device that is not cleared by Health Canada and claiming it is my device and potentially harming patients. I'm very upset about that," Graham says.

Health Canada has no record of any medical device being approved under Dupont's name.

Dupont created 'unique' device

A real HyProCure titanium stent is placed in the gap between foot bones, usually to help with flat feet. (Aadel Haleem/CBC ) After hearing the reports, Graham emailed Dupont, who had taken the HyProCure training, to ask if that was the case.

"[I] asked him by any chance, are you making a copy of HyProCure? He responded late that night ... that in fact he had been," adding he created a "unique" device, Graham told CBC News, in an interview at his office in Macomb, Mich.

In an email to Michael Graham of GraMedica, Pierre Dupont says he has created his own 'unique' stent. (CBC)

"I don't know what the sterilization is, I don't know what kind of issues this is going to raise going forward. He's basically lying to his patients, misleading his patients, putting in an experimental product."

Graham says the real HyProCure implant is used in 60 countries and on tens of thousand of patients with few problems.

He says Dupont has purchased implants from his company, so GraMedica is now working to figure out which patients got those stents and which could have the others.

"We really don't know how many people have fake implants," he says. "We will find out eventually."

GraMedica has dropped Dupont from its list of recommended HyProCure surgeons, and Graham says he is also seeking legal recourse to stop Dupont from using the HyProCure name.

Michael Graham, inventor of the HyProCure stent, says anyone who has a real stent will have an ID card with the device's lot number. (Aadel Haleem/CBC )

Through his lawyer, Dupont issued a statement to CBC.

"Given that the matters reported on by the media in recent weeks are the subject of confidential complaints that are ongoing before the College [of Chiropodists of Ontario], it would be inappropriate to discuss them in public or in the media. I would encourage everyone to keep an open mind and not rush to judgment. There is another side to this story which will become known once these matters are resolved."

Family paid almost $7,000 for implants

Dupont was paid almost $7,000 for putting HyProCure implants in the feet of Maryse Pagé's eight-year-old son Francis to fix a problem with flat feet. After months of problems with one implant, Dupont removed it. The procedure, that usually takes about 20 minutes, took more than an hour, Pagé says.

"I started to hear him screaming and crying and it lasted very long and I was on my knees praying for him to be safe," Pagé says.

Maryse Pagé worries her eight-year-old son may have an untested and unapproved implant in his foot. (Laurent Racine/CBC)

CBC News obtained the boy's medical file, which includes identification numbers for the implants used. GraMedica says those ID numbers don't match authentic HyProCure ones.

The boy's records also show he was given a size 8½ implant. HyProCure stents don't come in half sizes. The boy will soon get the other implant removed by an Ottawa podiatrist, who told the family he is curious to find out what the stent is made of.

Erika Brathwaite's left foot after the stent was put in. Though Pierre Dupont eventually took it out, she now has problems she didn't have before surgery. (Erika Brathwaite)

Erika Brathwaite, another of Dupont's former patients, first contacted Go Public late last year after he put a stent in her left foot that led to pain and difficulty walking.

Her medical file includes the ID number for a legitimate HyProCure implant, but is missing other authentication measures — including a validation sticker and ID card that states the implant is a real HyProCure stent.

"I really thought I was getting one thing, and it turns out I may not have gotten that. It's reprehensible. I can't even believe it," Brathwaite says.

She may never know, because Dupont removed the stent in November. Brathwaite says she still has pain in her foot.

Dupont banned from using stents

The College of Chiropodists of Ontario has now put a restriction on Dupont's licence.

"Mr. Dupont may not perform any procedure on a client involving the use of a stent," a statement on the college's website says.

The college won't say why the limitation was put in place or who requested it, only that Dupont voluntarily agreed to the restriction.

CBC News has learned six of Dupont's patients have filed complaints with the college.

Lawyer Craig Brown has been contacted by about a dozen of Pierre Dupont's former patients to investigate the possibility of legal action against the podiatrist. (Tina Mackenzie/CBC)

"I am collaborating fully with the college and will respond in due course to the allegations made by these complainants," Dupont says in his statement to Go Public.

"I am confident that the college will conduct a full and fair review of the allegations and complete its work in a timely fashion. It would be unfair to the process for me to comment on the merits of the complaints until such a time as the college has completed its work and given its ruling."

Legal action considered

About a dozen of Dupont's former patients have hired a Toronto law firm to investigate the possibility of a group action against him.

"The first contact we had was from a family who brought their 11-year-old son to Dr. Dupont for treatment for his flat feet. We have since heard from a wide range of people, in the sense of ages and geographic location," says Craig Brown, a partner at Thomson Rogers.

Brown says the complaints are from patients who have had implants put in by Dupont and say they are left with pain and, in some cases, difficulty walking.

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