Knee resurfacing using the Mako surgical robot from July 2016.

From July 2016, Professor Bill Walter will begin using the new Mako Surgical Robot at the Mater Hospital.  The Mako is a robotic arm. It assists in the precise preparation of the bone for the placement of a uni-compartmental knee replacement. The technology has been shown to improve the precision of this difficult surgery with resulting benefits for patients. With the robot, the surgery can be performed more safely and reliably and with better outcomes. This is an exciting step forward.

What is uni-compartmental Knee Replacement?

Unicompartmental knee replacement or unicompartmental knee resurfacing is a type of partial knee replacement. This is where just one of the two femorotibial compartments is replaced – usually the medial compartment (inside of the knee).

Uni-compartmental knee replacement involves replacing only part of the knee joint – usually the medial compartment (right side of the left knee). A small incision is made next to the patella tendon. Diseased bone and cartilage are removed from the tibia and femur. A metallic component is then attached to the femur. On the tibial side, a polyethylene component is attached directly to the bone or a metallic component is attached to the tibia and polyethylene insert is placed between the parts.

A unicompartmental knee replacement is a smaller operation than a total knee replacement with less pain, less blood loss and a faster recovery. Patients are usually on their feet walking within 6 hours of the surgery and stay in a hospital for 2 to 4 days.

Unicompartmental knee replacement is only appropriate where the arthritis is isolated to one compartment of the knee. Age, gender, activity levels and body mass are also a consideration. Take the Knee Quiz to find out how your knees rate.

Superior functional results are achieved after unicompartmental compared to total knee replacement. However, unicompartmental knee replacement carries a greater risk of revision surgery than primary total knee replacement but revision surgery is easier because there is usually a more preserved bone.