When knee joints are injured or simply become worn out, a knee replacement surgery can often be the best procedure. Knee replacement eases pain and allows the knee to regain better function. The surgery involves removing damaged bone and cartilage and replacing it with parts made of plastic and/or metal.
Your surgeon will evaluate your knee for stability, range of motion, and strength to determine if a knee replacement is right for you.
The knee is a complex hinge-type joint which is formed by the articulation of the femur (thighbone), tibia (shinbone), and patella (kneecap). It also consists of various muscles, tendons, ligaments, and cartilage.
There are 4 main ligaments of the knee which serve to stabilize the joint throughout range of motion. The medial collateral ligament and lateral collateral ligament exist on either side of the knee and provide stability from a side-to-side motion. The anterior cruciate ligament and posterior cruciate ligament exist within the knee and provide rotational and front-to-back stability to the joint. Injury to one or more of these ligaments can cause significant pain but also the feeling of knee instability.
The surfaces of the femur, tibia, and patella are lined with articular cartilage which enables the joint to move smoothly and freely. Deterioration of this smooth cartilage lining can be very painful and debilitating for patients. This can be due to a variety of reasons including arthritis (osteoarthritis or rheumatoid arthritis), trauma, infection, and other specific conditions. Another cartilage structure called a meniscus also exists between the articular cartilage on both the inside and outside aspects of the knee. These C-shaped structures provide added stability to the knee as well as act as shock absorbers within the joint. Damage to these menisci can be quite painful for patients as well.