Defective hip replacements have been in the news a lot recently. Most of the concern has surrounded premature failures of metal-on-metal hip replacement implants, such as <"http://www.yourlawyer.com/topics/overview/DePuy-Hip-Implant-Recall-Johnson-and-Johnson">DePuy Orthopaedic’s ASR XL Acetabular Hip Replacement System, which was recalled this past August. Recent studies have raised concerns that metal-on-metal hip implants are causing tissue damage and other serious complications that can lead to life-long disability. To help hip implant recipients better understand the issues surrounding metal-on-metal hip replacements, we’ve compiled answers to the eight most important questions hip implant recipients should be asking about all-metal devices.
1. What is a Metal-on-Metal Hip Implant?
In metal-on-metal hip replacement, the articulating surfaces are made from cobalt-chrome, which purportedly offers high wear resistance and has much smaller debris particles than those with metal-on-plastic devices. Some metal-on-metal hip implants include Wright Medical’s CONSERVE Total Hip System, Biomet’s M2a Metal Hip, Zimmer Orthopedicsâ€™ Metasul, and of course, the now recalled DePuy ASR XL Acetabular Hip Replacement System.
2. What are the Safety Issues with Metal-on-Metal Hip Implants?
According to a New York Times report published in March 2010, metal-on-metal hip implants have been used in about one-third of the approximately 250,000 hip replacements performed annually in this country. However, many of the nation’s leading orthopedic surgeons have reduced or stopped use of these devices because of concerns that they can cause severe tissue and bone damage. According to the Times, studies in recent years indicate that in some cases the devices can quickly begin to wear, generating high volumes of metallic debris that is absorbed into a patientâ€™s body. This can lead to serious reactions called periprosthetic metallosis and arthroprosthetic cobaltism. The limited studies conducted so far on metal-on-metal hip implants estimate that 1 to 3 percent of implant recipients could be affected by such problems.
3. What is Periprosthetic Metallosis?
Periprosthetic metallosis is a foreign-body reaction that is often diagnosed when victims of failed metal-on-metal hip implants undergo revision surgery. The metal-on-metal abrasion responsible for the condition releases a tremendous amount of particulate debris. The condition can cause an immune response that can lead to bone destruction, as well as the extensive formation of noncancerous tumors called granulomas.
4. What is Arthroprosthetic Cobaltism?
Arthroprosthetic cobaltism is a type of cobalt poisoning that results from the wearing of metal-on-metal hip implants. Left untreated, cobaltism can result in tinnitus, vertigo, deafness, blindness, optic nerve atrophy, convulsions, headaches, peripheral neuropathy, cardiomyopathy, and hypothyroidism. Late last month, the online American edition of the Journal of Bone and Joint Surgery (JBJS) published a case study regarding two patients who received metal-on-metal total hip replacements and experienced adverse events. After the revision surgeries, the symptoms improved. Both patients were fit, healthy 49-year old males. Their experience reports that cobalt toxicity – arthroprosthetic cobaltism – developed within their bodies after the all-metal devices were implanted. The case report states that a larger group study will be required to define the prevalence and spectrum of cobalt poisoning due to hip arthroplasty.
5. What are the Symptoms of a Failed Metal-on-Metal Hip Implant?
If you experience any of the following symptoms after the usual healing period following hip replacement surgery, you may be the victim of a failed metal-on-metal hip implant:
â€¢ Swelling, Extreme Pain & Discomfort
â€¢ Dislocation of Implant
â€¢ Clicking, Popping or Grinding
â€¢ Loosening of the Implant
â€¢ Unexplained Hip Pain
â€¢ Thigh Pain or Groin Pain
â€¢ Pain with Walking
â€¢ Pain Rising from a Seated Position
â€¢ Pain with Weight Bearing
One thing to keep in mind is that hip replacement patients should be relatively pain-free three months after surgery. Any new pain or increase in pain at that point should be promptly communicated to your surgeon, as it may indicate a complication.
6. What Should I do if I Have a Metal-on-Metal Hip Implant?
The American Academy of Orthopedic Surgeons recently recommended that patients with metal-on-metal hip implants inform all medical care givers about their joint replacement device and pay attention to post-operative pain. They should also speak to their doctor or surgeon if they notice new pains or medical concerns.
7. What About Testing for Cobalt Levels?
In April, European regulators announced they would be conducting a review of 40,000 metal-on-metal hip replacements over fears that the devices could cause non-cancerous tumors and tissue damage. At the time, officials with the United Kingdomâ€™s Medicines and Healthcare Products Regulatory Agency (MHRA) said anyone considered at risk would be given tests to establish whether there are high levels of metal compounds in the blood.
The American Academy of Orthopedic Surgeons says patients should discuss the value of such testing with his or her surgeon. At present, the testing has not been standardized and must be done by labs that specialize in trace metal analysis.
8. What if I Need Revision Surgery?
Recovery from revision surgery may take longer than recovery from a normal hip replacement. Sadly, in many cases, when a metal-on-metal hip implant fails, the accompanying tissue damage does not allow for complete recovery, and patients are left with some form of disability or residual pain.
If you do have to go through a hip replacement revision because of a failed metal-on-metal implant, it is vital that you retain the hardware from your original surgery. In the case of the recalled DePuy ASR XL Acetabular Hip Replacement System, the device maker confirmed that in order to be reimbursed for doctorâ€™s costs, X-rays and any repair surgery, patients must agree to provide DePuy with all medical records, as well as the faulty hip implant. However, attorneys are warning that surrendering the original hardware could hamper patientsâ€™ defective product claims should they decide to file suit against DePuy.