The National Institute for Health and Clinical Excellence (NICE) has issued full guidance to the NHS in England, Wales, Scotland and Northern Ireland on Arthroscopic knee washout, with or without debridement, for the treatment of osteoarthritis in August 2007.

Further recommendations have been made as part of the clinical guideline on osteoarthritis published in February 2008, as follows:

Referral for arthroscopic lavage and debridement should not be offered as part of treatment for osteoarthritis, unless the person has knee osteoarthritis with a clear history of mechanical locking (not gelling, 'giving way' or X-ray evidence of loose bodies).

Clinical and cost-effectiveness evidence was reviewed in the development of this guideline which has led to this more specific recommendation on the indication for which arthroscopic lavage and debridement is judged to be clinically and cost-effective. More information is available from NICE guideline CG59. The IP guidance on arthroscopic knee washout, with our without debridement, for the treatment of osteoarthritis remains current, and should be read in conjunction with the clinical guideline.


Osteoarthritis of the knee can cause pain, stiffness, swelling and difficulty in walking. An arthroscopic knee washout involves flushing the joint with fluid, which is introduced through small incisions in the knee. The procedure is often done with debridement, which is the removal of loose debris around the joint.

Coding recommendations

The code will be dependent on what has been carried out. Codes available are:

W85.1 Endoscopic removal of loose body from knee joint

W85.2 Endoscopic irrigation of knee joint

A code from category W80.- Debridement and irrigation of joint plus Y76.7 Arthroscopic approach to joint plus Z84.6 Knee joint

W85.8 Other specified therapeutic endoscopic operations on cavity of knee joint

W83.3 Endoscopic shaving of articular cartilage plusZ84.6 Knee joint

W82.2 Endoscopic resection of semilunar cartilage NEC

Note: Where both irrigation and removal of loose bodies are performed during the same procedure, then it is only necessary to record W85.1 Endoscopic removal of loose body from knee joint.

In addition an ICD-10 code from category M17.- Gonarthrosis [arthrosis of knee]  would be recorded.