Study design
Randomised, double-blind, placebo-controlled study.

Chronic tendon disorder is a major problem for many athletes and conservative treatment varies substantially. A treatment method with essential fatty acids and antioxidants combined with physiotherapy has attracted some attention and is evaluated in this study.

Methods and measures
In a randomised, double-blind, placebo-controlled trial 40 volunteers active in recreational sports with chronic tendon disorders were assigned to the study. The subjects were divided in two groups, one consuming a daily dosage of essential fatty acids and antioxidants and one consuming similar placebo. Furthermore, the subjects received 16 sessions of ultrasound treatment over 32 days. Evaluation was pain scores, rated on a visual analogue scale and quantification of normal sports activity during treatment.

In the treatment group there was a significant reduction of pain compared with the placebo group (P<0.001) after 32 days. There was a mean decrease in pain score of 99% in the treatment group compared with a mean decrease of 31% in the placebo group. Sport-specific activity increased by 53% in the treatment group and increased by 11% in the placebo group.

The results suggest beneficial effect of essential fatty acids and antioxidants in combination with physiotherapy treating chronic tendon disorders.