Twenty-five years ago I had an arthroscopic surgery on my left knee. They made a 4-inch incision to remove a cartilage tear. I was recently diagnosed with a cartilage tear in my other knee. I have been told that this surgery can be done through three small incisions using the arthroscope. Please explain.

Arthroscopic surgery has come a long way since your first knee surgery 25 years ago. Back then, a long thin tube was inserted into your knee through a small incision. The surgeon then looked into the knee joint through an eyepiece on the arthroscope to diagnose knee injuries. If a knee injury such as a cartilage tear was diagnosed, a standard surgery was performed to remove the torn cartilage. As technology has advanced, more-sophisticated arthroscopic equipment and surgical techniques have been developed to give the surgeon the ability to diagnose problems and treat them with arthroscopic surgery. Visualization is now produced by a special camera attached to the arthroscopic lens. This allows for transmission of images from inside the knee onto a television screen, eliminating the use of an eyepiece. Instruments have been developed to pass through small arthroscopic incisions, eliminating the need for a large open incision. Instead of a 4-inch incision, you can expect three incisions about a quarter-inch each, less pain and a faster recovery.