Total Knee Replacement

What is a Total Knee Replacement?

To best understand your total knee replacement surgery, it is important to know how your knee works. A total knee replacement produces an artificial joint that functions similar to your natural knee. A total knee replacement can also help individuals return to their lifestyle, often pain free. Although the idea of getting an artificial knee joint may be intimidating, it is one of the safest and most effective medical procedures.

Your knee joint works like a hinge at the junction of two bones: the thigh bone (femur) and the shin bone (tibia). The ends of the bones are normally covered with a thick cushion of soft white cartilage. If this cartilage is damaged or worn away, the underlying bones rub together, causing the pain and inflammation of arthritis.

“Arthritis” is an inflammation of a joint causing pain, swelling, stiffness, instability and often deformity. Severe arthritis interferes with a person’s activities and limits his or her lifestyle.

The primary reason for a total knee replacement is to reduce pain and improve your quality of life. It may also help to restore smooth motion, straighten the leg, improve stability, and improve the function of the joint.

In total knee replacement the surface of the joint is replaced with metal and plastic surfaces, which can function similar to a normal joint. This is accomplished by surgically trimming off the arthritic ends of the bones and replacing them with new metal and plastic surfaces. In reality, a total knee replacement is a “resurfacing” of the joint. Most of the supporting ligaments, tendons and muscles around the knee are retained. The new joint’s surfaces will mimic the natural knee it replaces.

Which Patients Should Have a Knee Replacement?

Total knee replacement is recommended for patients with arthritis who have severe pain and limited function, which significantly affects quality of life. The most common reason to have a total knee replacement is to relieve arthritis pain. The pain may not be excruciating at any particular time, but it is often chronic and disabling. Everyone’s pain is different, and the degree of pain sufficient to justify surgery should be decided by the patient and Mr. McKenna together.

Painful and arthritic knees can become unstable, causing falls and other injuries. Climbing stairs, getting up from chairs and extended walking can all be difficult.

While most arthritic knees are the result of degenerative arthritis or osteoarthritis other conditions such as rheumatoid arthritis, trauma, prior surgeries, instability and tumours can also be relieved by total knee replacement.

What is the Long-term Prognosis for Total Knee Replacement?

On an individual basis it is impossible to predict how long a knee replacement will last. With newer materials and techniques, the lifespan of knee replacements continues to increase. Over time, a certain percentage of patients having a total knee replacement will require revision surgery. Although uncommon implants can develop mechanical problems such as loosening, fracture, or wear. Other problems (i.e. infection or instability) can also develop and lead to the need for revision surgery.

Potential Medical and Surgical Complications

While Mr. McKenna always attempts to fully explain the nature and purpose of knee replacement, its benefits, possible non-surgical alternative methods of treatment, the risks involved, and the possible complications, he cannot guarantee or assure that complete restoration of function will be achieved as a result of your knee replacement. The risks and potential medical and surgical complications include but are not limited to the following: infection, blood clot formation in the leg or lungs (venous thrombo-embolism), death, dislocation, persistent pain (10-20%), stiffness, instability, limp, weakness, breakage of bone or parts, uncontrolled bleeding, nerve injury, blood vessel injury, delayed wound healing, wear, loosening and pressure sores. Anaesthetic risks are also present as well as the risk of needing a blood transfusion.