Experts advise against surgery for almost all patients with degenerative knee damage

Knee arthroscopy (keyhole surgery to relieve pain and improve movement) should not be performed in almost all patients with degenerative knee disease, say a panel of international experts in The BMJ today.

Their strong recommendation against surgery is based on new evidence that it does not, on average, result in a lasting improvement in pain or function - and they say further research is unlikely to alter this advice.

Their advice is part of The BMJ's 'Rapid Recommendations' initiative - to produce rapid and trustworthy guidance based on new evidence to help doctors make better decisions with their patients.

Degenerative knee disease (commonly known as arthritis) is a chronic condition in which symptoms fluctuate. Knee arthroscopy is one of the most common surgical procedures. Every year, an estimated two million people worldwide undergo knee arthroscopy at a cost of $3bn per year in the US alone. Yet current evidence suggests that arthroscopic knee surgery offers little benefit for most patients and is not cost effective.

For example, a trial published in The BMJ in 2016 showed that among patients with meniscus tear (damage to the rubbery discs that cushion the knee joint), surgery was no better than exercise therapy.

Yet, despite there being no evidence that arthroscopy is beneficial in any patient group, most guidelines continue to support the use of arthroscopy in key subgroups, including those with meniscus tear, sudden onset of symptoms (such as pain or swelling), or mild-moderate difficulties with knee movement. Most people with degenerative knee disease fit into at least one of these subgroups.

So an international panel - made up of bone surgeons, physiotherapists, clinicians and patients with experience of degenerative knee disease (including those who had undergone and those who had not undergone arthroscopy) decided to carry out a detailed analysis of the latest evidence.

Their rapid recommendation package includes a systematic review (published in BMJ Open) which adds the 2016 trial to the existing body of evidence, and a review of patients' preferences on knee disease (also published in BMJ Open). These data were used as the basis for the recommendation.

Using the GRADE approach (a system used to assess the quality of evidence), they found that arthroscopic knee surgery does not, on average, result in an improvement in long term pain or function to all or almost all patients with degenerative knee disease.

In addition to the burden of undergoing knee arthroscopy, they say there are rare but important harms, although exactly how common these are is uncertain (low quality of evidence).

As such, they strongly recommend against arthroscopy for almost all patients with degenerative knee disease - and suggest that non-use of knee arthroscopy can be used as a performance measure or tied to health funding.

It is unlikely that new trials will alter the evidence, they add.

Casey Quinlan, a patient panel member said: "Knee arthroscopy has been oversold as a cure-all for knee pain. Participating in the working group that developed this guideline allowed for actual patient experience to be considered - mine was nowhere near what I had been told it would be, function and pain level were only marginally improved? - giving real outcomes as a basis for the recommendations. The goal was to make it possible for people exploring this knee arthroscopy with their doctors to have a clearer view of when it might be helpful to them, or unnecessary surgery."