It is easy to forget what a rarity hip replacement surgery used to be. Today, people with artificial hips are ubiquitous. Direct costs of hip and knee replacements exceed $35 billion in the United States. More than 285,000 hip replacements are performed annually in the United States and it is projected that total joint replacement will increase to 4 million patients annually due to the aging population. Until very recently, hip replacements have been applauded as a wonderful, revolutionary way to get people back on their feet with less or no pain. But with this revolution came medical device makers looking to make as much money, and get as much market share, as possible.
The temptations for hip makers was extraordinary. Hip replacement surgery may be recommended in cases where hip pain limits daily activities, continues while resting (night or day), limits the ability to move or lift the leg, or in cases where pain relief is not provided by physical therapy, walking supports or anti-inflammatory drugs. Hip replacement surgery has a high rate of success, due to improvements in surgical techniques and technology. Total hip arthroplasty (total hip replacement) involves removing the damaged bone and cartilage and replacing it with prosthetic components. These components did not come cheaply but health insurance companies readily admitted that this was the appropriate treatment for people with compromised hips.
Though many hip replacement surgeries are successful, there is risk for infection, failure, and other adverse effects. Concerns have been raised in peer reviewed publications relating to metallosis, the build up of metal debris in soft tissues or blood. Reports are generally restricted to metal-on-metal devices, or those constructed with acetabular polyethylene liner. Metal-on-metal devices often contain cobalt or chromium. Although the occurrence is rare (occurring in approximately 5.3% patients), it is a serious complication associated with these devices. Metallic debris can occur due to malpositioning of the implant, subluxation, or jamming of the femoral head.