Metal on Metal Artificial Hips Scrutinized

Once thought to be more durable and effective, metal on metal hip replacements are being questioned by orthopedic surgeons who are finding that these artificial hips are not lasting as long. The metal on metal devices are wearing out and causing metallic debris, bone loss, and the destruction of soft tissue. Such devices are also used in so-called hip resurfacing procedures. The problem has become significant enough that a recent editorial in The Journal of Arthroplasty has suggested that doctors use the metal on metal devices with “great caution, if at all.”
These devices are relatively new since they’ve only been used in the last decade and some studies suggest that 1 to 3% of the hip replacement population may be affected by the problem. Still, that may account for thousands of hip patients in the US.
According to the NY Times, surgeons at Rush University Medical Center have performed two dozen revision surgeries in the past year. The Mayo Clinic reports similar numbers of patients with problems resulting from metal debris. The metal debris, primarily cobalt and chromium, can be absorbed in surrounding tissue or enter the blood stream. Symptoms of metal on metal problems include inflammation of the joint, bone loss, and pain in the groin area.
According to the Times article, all major hip device makers sell these metal and metal devices and some have responded to the concern over them. Zimmer Holdings, one of the country’s largest hip device manufacturers, has sought to downplay to significance of the issue as well as the potential risk to patients.