Partial knee replacement, also known as unicompartmental knee arthroplasty (UKA), is a surgical procedure that replaces only the damaged compartment of the knee joint. Unlike total knee replacement, which resurfaces the entire knee, this approach targets the specific area affected by arthritis while leaving healthy tissue intact.
The knee joint consists of three compartments: the medial (inner) compartment, the lateral (outer) compartment, and the patellofemoral (front) compartment between the kneecap and thighbone. Partial knee replacement addresses arthritis isolated to one of these compartments, most commonly the medial compartment.
During the procedure, your orthopaedic surgeon removes the damaged cartilage and bone surfaces from the affected compartment and replaces them with metal and plastic components. These implants recreate a smooth, functional joint surface that supports comfortable movement.
This procedure may be suitable for patients with osteoarthritis (wear-and-tear arthritis that breaks down joint cartilage) confined to one area of the knee. By preserving the healthy portions of the joint, including the cruciate ligaments (bands of tissue that stabilise the knee), partial knee replacement can often result in more natural knee movement and sensation compared to total replacement.