Knee replacement surgery replaces parts of injured or worn-out knee joints. This also is known as knee arthroplasty. During the surgery, damaged bone and cartilage are replaced with parts made of metal and plastic.
Knee replacement surgery can help ease pain and make the knee work better. To decide whether a knee replacement is right for you, a surgeon checks your knee’s range of motion, stability and strength. X-rays help show the extent of damage.
The right artificial joints and surgical techniques needed depend on many factors including age, weight, activity level, knee size and shape, and overall health.
The most common reason for knee replacement surgery is to ease pain caused by arthritis. People who need knee replacement surgery often have problems walking, climbing stairs and getting up out of chairs.
If only one part of the knee is damaged, surgeons often can replace just that part. This is called a partial knee replacement. If the entire joint needs to be replaced, the ends of the thighbone and shinbone are reshaped, and the entire joint is resurfaced. This is called a total knee replacement. The thighbone and shinbone are hard tubes that contain a soft center. The ends of the artificial parts are inserted into the softer central part of the bones.
Ligaments are bands of tissue that help hold joints together. If the knee’s ligaments aren’t strong enough to hold the joint together by themselves, the surgeon may choose implants that can be connected so they can’t come apart.