The goal of knee replacement surgery is to decrease pain and restore function. Although total knee replacement (also called “arthroplasty”) is an excellent option for patients with osteoarthritis of the knee, other surgical options exist. Patients with osteoarthritis that is limited to just one part of the knee may be candidates for unicompartmental knee replacement (also called a “partial” knee replacement).
Partial replacements are becoming more attractive to patients due to:
- Higher patient satisfaction
- Preserving more normal knee motion
- Less blood loss during surgery
- Faster recovery time
To determine whether you may benefit from a partial knee replacement, Dr. Backe will conduct a thorough orthopedic evaluation.
Your doctor will ask you several questions about your knee pain. He or she will be specifically concerned with the location of your pain. If your pain is located almost entirely on either the inside portion or outside portion of your knee, then you may be a candidate for a partial knee replacement. If you have pain throughout your entire knee or pain in the front of your knee (under your kneecap) you may be better qualified for a total knee replacement.
Your doctor will closely examine your knee. He or she will try to determine the location of your pain. Your doctor will also test your knee for range of motion and ligament quality. If your knee is too stiff, or if the ligaments in your knee feel weak or torn, then Dr. Backe will probably not recommend unicompartmental knee replacement (although you still may be a great candidate for total knee replacement).
Your doctor will order several x-rays of your knee to see the pattern of arthritis. Some surgeons may also order a magnetic resonance imaging (MRI) scan to better evaluate the cartilage.
Your surgeon will make an incision at the front of your knee. He will then explore the three compartments of your knee to verify that the cartilage damage is, in fact, limited to one compartment and that your ligaments are intact. If Dr. Backe feels that your knee is unsuitable for a partial knee replacement, he will instead perform a total knee replacement. He will discuss this contingency plan with you before your operation to make sure that you agree with this strategy.
If your knee is suitable for a partial knee replacement, Dr. Backe will use special saws to remove the cartilage from the damaged compartment of your knee and will cap the ends of the femur and tibia with metal coverings. The metal components are generally held to the bone with cement. A plastic insert is placed between the two metal components to allow for a smooth gliding surface.