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What Causes Hip & Knee Pain?

Many Americans are plagued with disabling hip and knee pain. Arthritis, a disease that can result from wear and tear on the joints, is one of the most common causes of pain.

Other causes of arthritis include trauma, dysplasia, osteonecrosis and inflammatory arthritis.

Total Hip Replacement

A total hip replacement is when the top part of the femur (ball section) is replaced along with the socket part of the pelvis. This is done by placing metal alloy on the top of the femur and the socket part of the pelvis. A smooth piece of cup-shaped plastic is inserted between this new ball and socket, which allows the ball to move smoothly. Replacement of the worn cartilage with the metal and plastic implant creates a new smooth cushion and a functioning joint. Although not a normal hip, a replaced hip provides significant relief from arthritis pain. Most patients have a marked decrease in their pain with substantial improvement in function, which allows them to remain active and enjoy activities that had been limited because of pain.

Total Knee Replacement

A total knee replacement is really cartilage replacement with an artificial surface. The knee itself is not replaced. An artificial substitute for the cartilage is inserted onto the end of each of the bones. This is done with a metal alloy on the end of the femur and tibia, with a medical-quality plastic inserted between them. The cartilage on the undersurface of the kneecap also can be replaced with plastic. Replacement of the worn cartilage with the metal and plastic implant creates a new, smooth cushion and functioning joint.

Although not a normal knee, a replaced knee provides relief from the arthritis pain. Most patients have a marked decrease in their pain with substantial improvement in function after a knee replacement, which allows them to remain active and enjoy activities that had been limited because of pain.

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