Joints are formed by the ends of two or more bones connected by a tissue called cartilage. Healthy cartilage serves as a protective cushion, allowing smooth, low-friction movement of the joint. If the cartilage becomes damaged by a disease or injury, the tissues around the joint becomes inflamed, causing pain. With time, the cartilage wears away, allowing the rough edges of the bone to rub against each other, causing more pain. This stage is called osteoarthritis, normally we know it as the wear and tear disease of joints.
When conservative treatments for advanced stage of osteoarthritis like lifestyle changes, medication and physical therapy have been exhausted, knee-replacement surgery is the procedure of choice. Knee-replacement surgery or knee arthroplasty, is a surgical procedure to replace damaged surfaces of the knee-joint to relieve pain and disability and correct mal-alignment of knee-joint. Knee replacement surgery can be performed as a partial or total knee-replacement. When there is a severally damaged osteoarthritic knee and the joint is completely degenerated, total knee-replacement surgery is the preferred procedure, but when patient’s osteoarthritis is limited to just one part of the knee, unicompartmental knee replacement (also called “partial” knee replacement) may be needed.
Our knee is divided into three major compartments: The medial compartment (the inside part of the knee), the lateral compartment (the outside part), and the patellofemoral compartment (the front of the knee between the knee cap and thighbone). In a unicompartmental knee replacement, only the damaged compartment is replaced with metal and plastic. The healthy cartilage, the ligaments and bone in the rest of the knee is left alone.
Advantages of Unicompartmental Knee Replacement (Partial Knee Replacement)
Minimal invasive surgery
Less pain after surgery
Less blood loss
Also, because the bone, cartilage, and ligaments in the healthy parts of the knee are kept, most patients report that a unicompartmental knee replacement feels more “natural” than a total knee replacement. A unicompartmental knee may also bend better.
The most common type of partial knee replacement is medial UKR because medial (inner side) part of knee gets degenerated first. As arthritis is becoming more common in young active patients who want to do sporting activities and lead a very active lifestyle, partial knee replacement gives them the option of having complete pain relieved life and at the same time, retain both ligaments of the knee, thus achieving normal function.