Cartilage Repair – Microfracture / OATS / MACI

By Dr Daniel Meyerkort, Knee Surgeon, Perth Orthopaedic & Sports Medicine Centre

What is cartilage repair?

Our joints are covered in super smooth cartilage known as Hyaline cartilage. This lets the joint move with very low friction and wear. Some patients sustain an injury that damages the cartilage (often a piece of cartilage is sheared off from the underlying knee). It is commonly associated with ACL or meniscus injury. This article discuss the various options available for cartilage repair. It should be stressed that cartilage repair does not work in patients with underlying arthritis (Cartilage repair is for young patients without arthritis, it has been tried as an alternative to knee replacement in patients with underlying arthritis and results have been poor).


Microfracture is the simplest of the cartilage repair techniques. It involves stabilising any loose cartilage around the defect then creating small holes within the bone to allow bleeding and stem cells to enter the defect. It has been shown to form fibrocartilage around the defect (not quite as strong as normal hyaline cartilage). Recent developments have allowed a microfracture to be combined with a biological scaffold to enhance the quality of the cartilage repair. The most commonly used bio scaffold in combination with microfracture is JointRep. Surgery is usually performed arthroscopically (keyhole). Depending on the size of the repair, a period of restricted weight bearing may be necessary for up to 6 weeks post surgery.