Partial Knee Replacement
During knee replacement surgery, damaged bone and cartilage is resurfaced with metal and plastic components. In unicompartmental knee replacement (also called “partial” knee replacement) only a portion of the knee is resurfaced. This procedure is an alternative to total knee replacement for patients whose disease is limited to just one area of the knee.
In the correctly indicated patients, people undergoing a partial knee replacement have a smaller incision, less pain, better range of motion, a quicker recovery, and a faster return to activity than patients undergoing a total knee replacement. Many patients also feel the partial knee feels more like a natural knee than the total knee replacement. In fact, most partial knee replacements can be done as an outpatient procedure.
This x-ray photo shows a partial knee replacement on the left and a full replacement on the right.
4 Signs You May Benefit from a Partial Knee Replacement
Arthritis pain tends to be deep and achy in nature. It typically does not radiate. Most knee pain is caused by three types of arthritis: osteoarthritis, rheumatoid arthritis, and post-traumatic arthritis.
- Osteoarthritis is an age-related “wear and tear” type of arthritis. It usually occurs in patient 50 years of age or older, but may occur in younger patients as well.
- Rheumatoid arthritis causes the synovial membrane that surrounds the knee joint to become inflamed and thickened. This chronic inflammation can damage the cartilage and eventually cause cartilage loss, pain, and stiffness.
- Post-traumatic arthritis can follow a serious knee injury. Fractures of the bones surrounding the knee or tears of the knee ligaments may damage the articular cartilage over time, causing knee pain and limiting knee function.
When patients have severe knee pain, they limit their range of motion to prevent causing discomfort in the knee. With time, the ligaments and muscles about the knee contract resulting in stiffness and loss of motion. The stiffness can limit a patient’s everyday activities, including walking, climbing stairs, bending or kneeling, and getting in and out of chairs. Ultimately, a patient’s pre-op range of motion determines his or her post-op range of motion, so it is important to keep as much motion in the knee prior to surgery.
Medical words that end in “itis” typically refer to some form of inflammation. In severe arthritis, the ends of the bones lose all their cartilage, and start to rub on each other producing inflammation. The inflammation results in swelling and pain. It is common for patients to notice that their knee swells after certain activities.
The arthritic cartilage and underlying bone have been removed from the knee and resurfaced with metal implants on the femur (thigh bone) and tibia (shin bone). A plastic spacer has been placed in between the metal implants. The undersurface of the patella is also cut and replaced with a piece of plastic.
The arthritic cartilage and underlying bone have been removed from the knee and resurfaced with metal implants on the femur (thigh bone) and tibia (shin bone). A plastic spacer has been placed in between the metal implants. The undersurface of the patella is also cut and replaced with a piece of plastic.
