Just two years ago, a five-year follow-up was performed on 52 randomized patients that had received either a metal-on-metal hip or metal-on-polyethylene hip implant. Tests confirmed an alarming 10- to 20-fold increase in cobalt and chromium levels in the systems of the patients who received the metal-on-metal hip implant.
Most hip implants last for 20 years or more. However, patients are reporting metal hip implants like the ASR metal-on-metal hip implants made by DePuy Orthopaedics, a subsidiary of Johnson & Johnson, are failing in only five years
Other metal-on-metal hip implant makers are Smith & Nephew, Wright Medical, Zimmer Biomet Holdings and Stryker. All have faced an onslaught of lawsuits alleging the devices result in problems including loosening, bone erosion, damage to surrounding tissue and metallosis, a dangerous blood condition that occurs when metal bits flake off the device and make their way into the bloodstream.
Physicians have been performing tests and studies on potential problems with metal-on-metal hips as early as 1994. Metal poisoning is a condition not to be taken lightly.
“Cobalt intoxication has been a well-known cause of cardiomyopathy for over 50 years, but primarily in the context of steel workers exposed to the metal industrially, or in cases of food or drink contaminated by cobalt,” says Dr Juergen R. Schaefer director of the Center for Undiagnosed Diseases in Marburg, Germany.
“Numerous studies have investigated metal exposure due to hip replacements,” Schaefer said, “but in certain situations – where the placement has gone wrong, where there are technical problems with the prosthesis, and strikingly often after an off-label replacement of broken ceramic hips by metal parts – patients are at risk of cobalt poisoning due to hip prosthesis, a problem which appears to be on the increase, and which can be life-threatening.”