Summary of intervention

Arthroscopic washout of the knee is an operation where an arthroscope (camera) is inserted in to the knee along with fluid. Occasionally loose debris drains out with the fluid, or debridement, (surgical removal of damaged cartilage) is performed, but the procedure does not improve symptoms or function of the knee joint.


Number of CCG intervention 2017/18




Arthroscopic knee washout (lavage and debridement) should not be used as a treatment for osteoarthritis because it is clinically ineffective.


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.


More effective treatment includes exercise programmes (e.g. ESCAPE pain), losing weight (if necessary) and managing pain. Osteoarthritis is relatively common in older age groups. Where symptoms do not resolve after non- operative treatment, referral for consideration of knee replacement, or joint preserving surgery such as osteotomy is appropriate.


For further information, please see:

NICE Interventional procedure overview of arthroscopic knee washout, with or without  debridement, for the treatment of osteoarthritis [IP366]

NICE Arthroscopic knee washout, with or without debridement, for the treatment of osteoarthritis [IPG230]

NICE Do not do recommendations

Escape Pain


Rationale for recommendation

NICE has reviewed the evidence for how well knee washout works for people with osteoarthritis. Seven clinical trials and three case studies have shown that knee wash out for people with osteoarthritis did not reduce pain nor improve how well their knees worked. There was a small increased risk of bleeding inside the knee joint (haemarthrosis) (2%) or blood clot in the leg (deep vein thrombosis) (0.5%).