A knee replacement surgery may be necessary if you have been experiencing severe knee pain and disability from rheumatoid arthritis, osteoarthritis, or traumatic injury. The principle behind this surgical procedure is simple: the orthopedic surgeon will replace your damaged knee with an artificial device, an implant, to somehow restore function and range of movement. It is a very common procedure and thousands are done each year.
What you should be more concerned of, ideally, is what implant to choose from. Manufacturers offer different models and features designed for a patient’s size and activity level. In fact, more than 150 different knee replacement devices now exist. It’s therefore wise to be proactive in learning about these different types and what might be best for you.
Knee replacement implants are made of metal alloys, ceramic material, or strong plastic parts, and can be joined to your bone. Metal components usually consist of titanium or cobalt-chromium based alloys. These materials are known for their durability, and have stable (inert) chemical properties such that they do not interact with the body. However, the most common material used to produce plastic components is ultra-high molecular weight polyethylene.
We also have fixed-bearing prosthesis and mobile bearing prosthesis. The former is the traditional method for implanting an artificial knee and it is often used for older patients while the latter preferred for younger patients because it is designed to accommodate a more active lifestyle.
Traditionally, manufacturers have designed knee implants based on “average” size data. However, recent developments in design include gender specific implants too. A number of studies indicate that the shape and proportions of a woman’s knee differ from those of a man’s knee. As a result, several manufacturers have developed components for the end of the thighbone which more closely match the average woman’s knee.
If you are overwhelmed with all of these available options, go talk to your orthopedic surgeon. He or she can answer your questions and can guide you in choosing the prosthetic device that fits and works best. He or she will need to consider your age, weight, anatomy, and activity level though. A conversation with your surgeon will definitely help you understand more of what you’ll be getting your knee replaced with.