Arthroscopic knee surgery. Close-up of an endoscopic view of an arthroscopic tool being used by an orthopaedic surgeon during keyhole surgery on a patient's knee. Keyhole surgery is minimally invasive, with endoscopes (called arthroscopes here) inserted through small incisions. This is less traumatic to the patient than full surgery to open up the knee joint. Arthroscopic surgery is often exploratory, using an endoscope and its camera to examine the knee and then carry out any minor surgery that may be needed. This can include lavage and debridement, where the surgeon identifies bone and cartilage fragments in the joint. These fragments will be flushed out, and bone tools used to smooth rough joint surfaces (as shown here). Such joint damage can be due to wear and tear, injury, or conditions such as arthritis. For a sequence of clips taken during this procedure, see K003/0152 to K003/0196.