Previous trials have shown that acupuncture can relieve pain, but many have been small and it is difficult to decide whether the benefits identified are simply the result of the placebo effect.

The German study, published in Arthritis & Rheumatism, compared the experience of 357 patients given immediate acupuncture with a further 355 whose treatment started three months later.

Benefits were measured on the WOMAC scale, a widely used scale of disease severity which measures pain, stiffness, and how well the joint works. At the start of treatment the patients’ scores on the scale were about 50.

After 15 sessions in the first three months, the patients treated with acupuncture had WOMAC scores of about 30, while the control group still waiting for treatment remained about 50.

After adjusting for other factors, the improvement in the score was 36 per cent. After six months the control group, which began its treatment three months later, showed the same level of improvement. In all cases normal care continued alongside the acupuncture treatments.

The researchers, led by Claudia Witte, of the Charité University of Medicine in Berlin, concluded that adding acupuncture to the normal treatment regimes — which generally consists of anti-inflammatory drugs — produced “a clinically relevant and persistent benefit”.

However, the results may not satisfy sceptics. The study was not a double-blind, and the experience of the acupuncturists did not have any influence on the outcome — inexperienced acupuncturists were just as effective as experienced ones. In an editorial in the journal, Tao Liu and Chen Liu, who teach Chinese medicine at Jilin University, in China, said that nothing was more important than the experience of the acupuncturist.

Despite this, the scientists said that the study was further evidence of the usefulness of acupuncture and warranted its extensive use in treating pain, although no one can yet explain how it works.

Partly as a result of the trial, the German Ministry of Health is considering a recommendation from a federal committee of doctors and health insurers that acupuncture should be covered by medical insurance.

Traditionally, German doctors have been far more enthusiastic about alternative treatments than their British counterparts. However, acupuncture is becoming increasingly popular in Britain and many physiotherapy departments in hospitals now offer the services of an acupuncturist.

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