Systemic Cobalt Poisoning Increasingly Recognized with Metal-on-Metal Hip Implants, Study ShowsJul 16, 2015
A review published in the Journal of Patient Safety evaluates systemic arthroprosthetic cobaltism, or systemic cobalt poisoning from arthroplasty implants, related to corrosion of chrome-cobalt hip implants. The researchers sought to identify all cases of systemic arthroprosthetic cobaltism through a systematic literature review.
The study found "a substantial increase" in reports of systemic arthroprosthetic cobaltism over the past three years, with a total of 25 patients between 2001 and 2004. There were a variety of symptoms among these patients: 84 percent had hip symptoms, 60 percent involved the cardiovascular system, 52 percent had symptoms involving the audiovestibular system, 48 percent involved the peripheral motor-sensory system, 48 percent had thyroid symptoms, 32 percent had psychological symptoms, 32 percent involved the visual system and 20 percent involved the hematological, oncological, or immune system. On average, presentation of symptoms or revision occurred 41 months after the hip was implanted. The average blood cobalt level was 324 ug/L. Blood cobalt, but not blood chromium, "was highly associated with a quantitative measure of overall symptom severity" the authors stated in the results.
The authors concluded that "Systemic arthroprosthetic cobaltism is an increasingly recognized complication of wear or corrosion of chrome-cobalt hip implants, may involve a large number of organ systems, and may occur with relatively low B[Co]. There is an urgent need to better define the overall scope of the problem and to develop screening and management strtegies."
Metal-on-metal hip implants have come under intense scrutiny in recent years. These devices were first marketed as being more durable and better suited for younger, more active patients. However, it has become clear that these devices can lead to a number of complications when the metal surfaces of the implant rub together, releasing metal particles into the bloodstream and nearby tissues. This can lead to a number of complications, including metallosis, prompting the need for an early revision surgery.
Metal hip devices are the subject of thousands of lawsuits filed in state and federal court. Parker Waichman LLP has filed metal hip implant lawsuits against Johnson & Johnson's DePuy Orthopedics, Stryker Orthopedics and Biomet on behalf of patients who suffered injuries, allegedly due to their metal-on-metal hip implants.