The knee joint, which appears like a simple hinge-joint, is one of the most complex joints. It consists of the femur (thighbone), tibia (shinbone) and patella (kneecap). The knee is a synovial joint, which means it is lined by synovium. The synovium produces fluid lubricating and nourishing the inside of the joint. Articular cartilage is the smooth surfaces at the end of the femur and tibia. It is the damage to this surface, which causes arthritis.
Arthroscopy is a surgical procedure in which an arthroscope is inserted into a joint. Arthroscopy is a term that comes from two Greek words, arthro-, meaning joint, and -skopein, meaning to examine.
Arthroscopy is performed in a hospital operating room under general anaesthetic.
The arthroscope is a small fibre-optic viewing instrument made up of a tiny lens, light source and video camera. The surgical instruments used in arthroscopic surgery are very small (only 3 or 4 mm in diameter), but appear much larger when viewed through an arthroscope.
The television camera attached to the arthroscope displays the image of the joint on a television screen, allowing the surgeon to look, for example, throughout the knee-at cartilage and ligaments, and under the kneecap. The surgeon can determine the amount or type of injury, and then repair or correct the problem, if it is necessary.
The surgeon makes two small incisions (about 1/4 of an inch), around the joint area. Each incision is called a portal. These incisions result in very small scars which in many cases are unnoticeable.
In one portal, the arthroscope is inserted to view the knee joint. Along with the arthroscope, a sterile solution is pumped to the joint which expands the knee joint, giving the surgeon a clear view and room to work. The sterile solution is regulated by a drainage needle for the amount of fluid in the joint during the procedure.
With the images from the arthroscope as a guide, the surgeon can look for any pathology or anomaly. The large image on the television screen allows the surgeon to see the joint directly and to determine the extent of the injuries and then to perform the particular surgical procedure if necessary.
The other portal is used for the insertion of surgical instruments. A surgical instrument is used to probe various parts within the joint to determine the extent of the problem. If the surgeon sees an opportunity to treat a problem, a variety of surgical instruments can be inserted through this portal. After treating the problem, the portals (incisions) are closed by suturing or by tape. Arthroscopy is much less traumatic to the muscles, ligaments, and tissues than the traditional method of surgically opening the knee with long incisions (arthrotomy).
Risks related to Arthroscopic knee surgery include:
The risks and complications of arthroscopic knee surgery are extremely small. One must however bear in mind that occasionally there is more damage in the knee than was initially thought and that may affect the recovery time. In addition if the cartilage in the knee is partly worn out then arthroscopic surgery has about a 65% chance of improving symptoms in the short to medium term but more definitive surgery may be required in the future. In general arthroscopic surgery does not improve knees that have well established Osteoarthritis.