Sulzer Hip Implants - Manufacturing Defect Revealed In Thousands of Artificial Joints

By LEIGH HOPPER
Copyright 2001 Houston Chronicle Medical Writer

One of the world's largest manufacturers of artificial joints has recalled thousands of defective hip replacement parts -- including those already implanted in an estimated 17,500 patients.

Austin-based Sulzer Orthopedics issued a recall Dec. 5, alerting surgeons, including some in Houston, to the possibility that patients have a faulty part that requires replacing. The company followed up with a letter mailed 18 days ago directly to patients.

So far, 91 people have had defective parts surgically removed and replaced, said Sulzer spokesman Jim Moore on Friday. Most of the patients with the recalled parts are in California, Texas, Arizona and Florida.

According to the company, an oily residue was left on the surface of an implant component because of a manufacturing error. In some cases, the residue caused inflammation, pain and prevented the patients' bones from fusing normally with the hip implant. Moore said the lubricant is mineral oil-based.

Symptoms, caused by a loose connection between the implant and the bone, include severe groin pain and an inability for the joint to bear weight.

Sulzer alerted the federal Food and Drug Administration to the problem Dec. 12 and has promised to cover any costs patients incur because of additional medical attention or a second operation.

A single hip replacement costs between $20,000 and $50,000, depending on patient age and length of hospital stay, most of which is paid for by Medicare and other health insurers. Doctors say the "revision" operation will be less complicated and will cost less.

"Anything that comes out of the patients' pockets, we're taking care of that," Moore said.

Dr. Kenneth Mathis, an orthopedic surgeon at the Arthritis Institute at Baylor College of Medicine, performed a revision operation on a patient Tuesday and has three more procedures planned. He said he has been working long hours since mid-December tracking down 124 patients with the recalled components and taking X-rays to assess their need for a second surgery.

"The vast majority of our patients are doing wonderfully," he said.

Estelle Knowland, 63, of Oakland, California, was surprised to learn there might be a problem with the routine hip replacement operation she underwent in March. Her orthopedic surgeon called on New Year's Day to tell her the artificial joint contained Sulzer's recalled component.

At this point, her problems are not severe; she said her bone recovery is 50 percent of what she would hope for, so she can afford to wait and see if her hip continues to heal.

"I was quite stunned and numb until I began to understand more about it," Knowland said. "I'm optimistic and I think I'll be OK."

Doctors replace approximately 125,000 hips a year in the United States and Sulzer is an industry leader in the replacement components. Arthritis -- rheumatoid in younger people and osteoarthritis in those over 60 -- is the most common reason for needing a new hip. As joint replacement operations go, hips are one of the most successful, with 98 percent of patients in some studies reporting excellent results 10 years after the operation.

Moore said Sulzer has "no way of knowing" how many people will require repairs. According to statement issued by Sulzer Orthopedics President Gary Sabins, "only a small number of patients" who received the hip replacement component, or shell, have experienced loosening of the shell.

"Please note that our surgeon advisers do not recommend that patients undergo removal of the part unless they exhibit symptoms of loosening," Sabins said.

A spokeswoman with the FDA said the agency is working quickly to classify the level of risk posed to patients by the defect and to evaluate whether the recall is being handled appropriately.

"We are aware of it and we are looking at it," she said.

Sulzer Orthopedics, which is part of Sulzer Medica, a multimillion-dollar international medical device company, began receiving reports in September about problems with its Inter-Op hip shell. The shell is implanted into the upper part of the hip, forming a socket into which the rest of the artificial joint fits.

Surgeons said patients implanted with the Inter-Op shell weren't healing properly. After ruling out surgical error and infection, Sulzer issued the recall.

"If healing doesn't take hold in six weeks after (the first) operation, we're recommending they talk to their physician," said Moore. "This company accepts responsibility for this failure ... Sulzer is doing everything possible to correct the problem for the patients and surgeons caught in the middle of this."

Mathis said the telephone calls have been difficult to make, breaking news to patients who become angry or upset upon learning they need another operation.