Knee surgery for arthritis patients may not be working, an international team of researchers says.
Keyhole surgery is meant to relieve pain and improve movement, but the researchers found for the cost of the operation, it had little to no effect across all patient groups.
Writing in the British Medical Journal, the experts even warned the "unnecessary surgery" could even do more harm than good, but more evidence is needed to distinguish how likely those harms are.
The caution comes from an international panel made up of bone surgeons, physiotherapists, clinicians and patients with experience of the degenerative knee disease.
Most health guidelines worldwide, including in New Zealand, continue to support the surgery for nearly all arthritis patients.
Casey Quinlan, a patient panel member said: "Knee arthroscopy has been oversold as a cure-all for knee pain. Mine was nowhere near what I had been told it would be."
Every year, an estimated 2 million people worldwide undergo knee arthroscopy.