What Is A Metal On Metal Hip Replacement?Hip replacement surgery is fast becoming one of the most common orthopaedic operations. Aimed at relieving suffering from a damaged hip, the procedure involves replacing the ball and socket of a damaged hip joint with an artificial implant. After the surgery the patient can hope to lead a pain free life with greater mobility and improved functioning of the hip joint. Hip replacement procedure is being developed and researched continually so as to make it easier for the patient. Traditionally hip replacement surgeries involve long periods of rehabilitation and patients have to face the risk of hip dislocation, fracture or loosening of the artificial hip after the surgery. Ongoing research is thus aimed at reducing these problems as much as possible. One of the major areas of development has been in the production of the hip implants. Different materials have been used and experimented with to make the implants with the aim of developing prosthetics that are durable in the long run and can withstand the wear and tear of continuous use. Durability is of special concern as it would imply that the artificial hip would take longer to loosen. Surgeons avoid revision operations if they can as they are not as successful as the first hip replacement surgery. Usually hip implants are made using a combination of metal and plastic. Commonly used implants have the ball and socket made of metal with a plastic spacer placed between them. To reduce the wear and tear on the prosthetics metal on metal implants were developed. It was found that by eliminating the plastic spacer, the implants would take longer to wear out. The metal on metal implants consists of a metal ball that fits into a metal cup. The surfaces are smooth, thus allowing the ball to glide in the cup. The metal used to make the implants can vary from titanium and stainless steel to cobalt chrome. Metal implants are particularly suited to those who lead an active lifestyle. For such patients the wear and tear on the hip joint is a lot and hence durability and resistance are of prime concern in choosing the right kind of hip replacement. These implants are also able to accommodate a larger femoral head. As a result the risk of dislocation is reduced and a greater range of movement assured to the patient. Metal on metal implants have come into existence in recent times. Extensive laboratory testing has found that the implants show promise of lasting longer than those made more conventionally of metal and plastic However there is not enough data generated from actual usage yet to support this claim. The other drawback is that the implants generate metals ions when the parts rub against each other. These ions can get released into the blood stream, allowing them to travel all over the body. It is thought that a build up of the ions could lead to cancer in the long run. However there is no concrete data to support this claim. |