Although the Zimmer Durom Acetabular Component Hip Implant was designed to minimize friction, improve patient mobility and eliminate hip pain, like many other metal-on-metal hip implants it has suffered its share of problems. The Durom Acetabular Component has been available in the United States since 2006, however a mere two years later, Zimmer Holding, Inc., sent out a warning to all medical professionals stating they would be conducting research within the company regarding the safety of the cup. This warning was in response to an extremely high number of patients who reported health complications from the implant.
Less than two months after the warning was issued Zimmer suspended the marketing and distribution of the Durom cup in the United States. Their explanation for this suspension was that surgeons required more training and more comprehensive instructions regarding implantation procedures. The suspension also stated that patients who experienced significant hip pain within three months post-implantation should immediately contact their physician. Zimmer did update surgical implantation instructions as well as launching its own surgical training program, returning the Durom Cup to the United States market under the cloud of claims of metallosis and metal toxicity.
As of December, 2012, Drug Watch reports that Zimmer has received numerous patient claims from recipients of the Durom Acetabular Component and, in 2008, created a $69 million dollar fund to pay patient claims meeting specific requirements in anticipation of those claims. It is estimated that over 12,000 people in the United States received the Durom Acetabular Component hip implant. Like other all-metal hip implants, when the metal components of the Zimmer Durom Acetabular rub against one another during times of physical activity, microscopic metal shards can be released. These metal ions can burrow into the surrounding tissues or can enter into the bloodstream of the implant recipient.
Metallosis occurs when the tissues become inflamed, causing the recipient considerable pain. Tissue death and bone loss can occur when the metal ions cause inflammation. Although the body will send out special white blood cells to combat what they perceive as a foreign invader, these cells are no match for ever-increasing amounts of cobalt and chromium. Aside from pain in the hip and groin area, limited mobility and the possibility of total hip failure, metal toxicity can lead to neurological issues such as memory loss, emotional disturbances including anxiety, depression and irritability, varying degrees of loss of vision and hearing, gastrointestinal, thyroid, cardiovascular and renal problems, loss of balance and vertigo and even alterations in patient DNA. Further, pseudo-tumors can occur, resulting in the necessity of a surgical procedure to remove them.
It is advisable for all recipients of the Zimmer Durom Acetabular Component hip implant—as well as recipients of other all-metal implants—have their blood monitored frequently for increased levels of cobalt and chromium. Other tests such as bone scans, x-rays and MRIs may also be recommended by the patient’s physician in order to determine whether the metal implant has caused problems in the recipient. Any unusual pain should be reported to the patient’s physician immediately.
Author:Andrew Sullo