Knee arthroscopy is commonly known as keyhole surgery. It involves a camera attached to a thin telescope that is inserted into the knee via a small incision of less than 1cm. With the camera, the surgeon can look inside the knee itself and identify any problems. If the camera reveals any problems the surgeon can use small instruments that can be inserted via a second small incision in the knee. Common problems that are treated by arthroscopic surgery include meniscal cartilage tears, worn articular cartilage and problems with the soft tissues within the knee joint such as synovial plicas. In addition, complex surgery such as cruciate ligament reconstruction can be performed using keyhole surgery techniques.
What happens in surgery?
The surgery is generally performed as a day case under a general anaesthetic. The operation usually takes around half an hour to perform although the time taken may be longer for more complex procedures. At the end of the operation your knee is injected with a local anaesthetic to minimise the post-operative pain.
Arthroscopic Meniscectomy & Meniscal repair
Meniscectomy involves trimming a torn cartilage using special keyhole surgical instruments. The meniscus is a crescent shaped rim of cartilage between the femur (thigh bone) and tibia (shin bone). If it is torn, it can catch in the knee causing pain. Only the torn part is removed, leaving the remaining uninjured cartilage behind. Arthroscopic meniscectomy has a high rate of success providing relief from knee pain. Where possible the meniscus is repaired using internal stitches, unfortunately this is the minority of cases and the failure of such repairs is one in four as the cartilage heals poorly.
Arthroscopic Microfracture & Chondroplasty
Damaged articular cartilage on the ends of the bones has very poor healing potential. Flaps of worn articular cartilage can catch as the knee moves and create pain and discomfort. ‘Chondroplasty’ involves trimming and smoothing these areas of cartilage, and so pain and mobility can be improved. Where there is a full thickness defect ‘microfracture’ may be beneficial which involves making small holes into the bone to release bone marrow cells and bleeding to promote healing which otherwise would not happen. It is important to recognise that worn articular cartilage is, potentially, the start of osteoarthritis in the knee and that your knee will not be returned to complete normality after this surgery.
Arthroscopic Soft Tissue Debridement
Sometimes folds of tissue in the lining of the knee can catch and become inflamed. These tissue folds are called plica. Not everybody has them and, even if you do, they may not be symptomatic. However, a plica may cause pain on the inside of the knee and around the patella. The plica can be trimmed with a small arthroscopic shaver and the symptoms relieved.
What happens after surgery?
You will be mobilised after surgery by a physiotherapist and will be able to walk out of the hospital a few hours after the surgery, although unable to drive for a few days or few weeks depending on surgery and leg involved. You will need to have outpatient physiotherapy for a few weeks after your operation to get your knee to settle and move as quickly as possible. Your mobility will improve each day after surgery. You will need a week or two off work depending on your job and the exact nature of the surgery. Your knee should be back to normal by 2-3 months depending on exactly what has had to be done.