Comparison of diclofenac sodium and aspirin in the treatment of acute sports injuries.

A randomized, double-blind, parallel-group clinical trial compared diclofenac sodium (Voltaren, Ciba-Geigy Summit, NJ) with aspirin for the treatment of acute sprains and/or strains of the knee or ankle. One hundred thirty-nine patients were admitted to the study. Patients received either 150 mg (75 mg twice daily) of diclofenac (N = 69) or 3.6 g (1.2 g three times daily) of aspirin (N = 70) for 3 to 10 days. Forty-seven diclofenac patients and 49 aspirin patients, mean age for both groups 25 years, were evaluated to determine the efficacy of each treatment. Both groups experienced significant (P less than 0.001) improvements for all efficacy variables measured. Treating sprains and strains with diclofenac rather than with aspirin allowed an earlier return to activity. Of those patients who achieved playing fitness, those in the diclofenac group resumed athletic activities in a mean of 4.7 days, compared with a mean of 5.9 days for patients in the aspirin group. Although the overall multivariate F was nonsignificant (P = 0.19), the univariate F for days required to resume playing fitness was significantly (P = 0.025) shorter in the diclofenac group. While the nonsignificant multivariate result suggests that the significance may be due to chance, it is also possible that there was a trend toward earlier resumption of activities with diclofenac treatment compared to aspirin, but an insufficient sample size to demonstrate the trend statistically. Since others have reported such a trend without the greater controls of a multivariate analysis, this area warrants further research.