An unusual cause of knee pain 10 years after arthroscopy.

Arthroscopic surgery, although relatively minimally invasive, is associated with specific complications. Cases of instruments retained in the knee joint after arthroscopy have been reported. There have been reports of scalpel blades detaching into the joint during the approach that were immediately retrieved, with or without arthrotomy. We report the case of a scalpel blade retained in the knee joint for 10 years after arthroscopy. This case demonstrates the need for the surgeon and the whole operating room staff to be aware of the instrumentation and to systematically check the instruments at the beginning, middle, and end of the procedure. The significance of reporting this case is to make the orthopaedic community aware of possible complications that can occur even with relatively "low-risk" procedures.