The hard articular cartilage in the knee can be torn by a bad fall, slow damage after a knee injury, general wear and tear or poor blood supply to the joint. It does not naturally repair itself. There are a number of arthroscopic procedures to deal with articular cartilage damage, the three most common being: chrondoplasty (see below), debridement and microfracture.

Once torn or damaged, fragments of the articular cartilage may break off, or the damaged surface may cause catching and locking, which can lead to inflammation of the joint. The inflammation can be painful and the sensation of catching and locking can make activities difficult.

The history and physical exam are usually enough to make a diagnosis. X-rays are taken to rule out fractures and an MRI scan may be used to confirm the tear.

During chrondoplasty, the damaged cartilage surface is cut, scraped, lasered or burred away. This procedure is designed to help stimulate the healthy joint surface to heal over the defect. The new surface is not actually articular cartilage (it’s called ‘fibrocartilage’), and is inferior to the original material. Because of this, chrondoplasty is usually used on smaller defects.

Articular cartilage heals poorly once it is damaged. Chondroplasty may stimulate the area to re-cover itself with new cartilage, the problem is that the new surface is not true hyaline or joint cartilage, but a rather inferior version called ‘fibrocartilage’. For this reason the technique is generally reserved for smaller defects.

The recovery period after this procedure is variable depending upon the size, position and severity of the lesion being treated. However, most heal up over a six week period.