An unusual recall of a hip replacement device has sparked class action lawsuits in Canada and the U.S. The makers voluntarily pulled the units in August, but some patients say they are only receiving the news now.

DePuy Orthopaedics, a unit of Johnson & Johnson, has issued a global recall of a metal hip socket, called the ASR XL Acetabular System, as well as a smaller hip resurfacing unit called the ASR Hip Resurfacing System.

While recalls of medical devices are not altogether new, the recall of a device that is fully implanted into the body during major surgery is unusual.

The "metal on metal" implants have been linked to higher failure rates. In some cases, the devices begin to wear, generating metallic debris that's absorbed into the body, touching off inflammatory reactions. About 13 per cent of patients needed a second hip replacement within five years of receiving an ASR implant.

About 93,000 of the devices have been implanted worldwide, including 1,500 or so in Canadians between 2006 and August 2010.

The Food and Drug Administration in the U.S. says it received about 400 complaints about the devices beginning in 2008. But the recall wasn't issued until this past August.

Now, some Canadian patients are filing lawsuits against the implant makers for pain and suffering they will have to endure because of the recall.

In Canada, two firms launched lawsuits this month: the litigation firm Teplitsky, Colson LLP and the Merchant Law Group.

"I think this is one of the most serious [lawsuits] because of the degree that people have to suffer to have the implant removed, and the recuperation that they have to undergo for a couple of years," says Teplitsky lawyer Harvin Pitch.

Hillary Berthelet is one of the patients affected. She had a hip implant three years ago and says she knew almost immediately that something was wrong.

"At a certain part of the motion of my leg, the joint would… clunk. There is no other word. It would clunk."

To weeks ago, she received a letter from her surgeon that her hip implant was being recalled.

"Physically, I felt like I had been kicked by a mule and I couldn't read any more of the letter. I was doubled over and I just had waves of nausea because I couldn't imagine they would recall it," she said.

Doctors agree the recall will create anxiety for anyone with the implants. But some surgeons estimate that only 30 to 40 Canadians will actually need the units removed. In most other cases, doctors say patients will simply have to be monitored for problems.

"Recall has the connotation that everybody has to come in and have their prosthesis removed. That is not the case. They just have to be recalled to be reviewed to make sure their prosthesis is working properly," says Dr. John Rudan, a professor of orthopedic surgery at Queen's University in Kingston, Ont.

Still, he notes that revision surgery on a hip replacement is a major surgery with a long recovery time.

"A revision of a component is bigger operation than doing the original procedure to put in the implant in the first place. A revision surgery is a much more difficult operation and more difficult for the patient to recover from," he said.

DePuy Orthopaedics says it understands that the recall is concerning for patients, their family members and surgeons, and says it is working with patients and their doctors to provide them with the information and support they need.

"DePuy intends to cover reasonable and customary medically necessary costs of testing and treatment for patients who need services associated with the ASR recall. DePuy will also pay for reasonable expenses related to receiving care, such as lost wages and travel costs," the company said in an email to CTV News.

Rudan says this case brings up a larger issue, which is the need for a registry for patients with medical devices. He notes that 50,000 medical implants are placed into Canadians each year, yet most patients have no clue of the brand of implant they've received.

As well, many don't ever know there's been a problem with their device until unless they are notified by their doctor or their hospital.

The country does have a joint replacement registry, operated through the Canadian Institute for Health Information (CIHI), but it is voluntary. It's estimated that only a fraction of artificial joints are added to the registry every year.

Rudan would like to see a mandatory system to register and track patients.

"Anything we can do to facilitate patients getting information in a timely manner is very important," he says.

*Patients who have received a hip replacement since 2006 should contact their surgeon or DePuy at 1-888-627-2677, to determine if they received an ASR implant.

*Patients who received their hip resurfacing/implant at Kingston General Hospital in Kingston, Ont. can call (613)549-6666, ext. 8220.

*Patients who received their hip resurfacing/implant at Montreal's Jewish General Hospital can call (514) 340-8222, ext. 4828.

With a report from CTV medical specialist Avis Favaro and producer Elizabeth St. Philip