ABSTRACT
INTRODUCTION: Lateral epicondylitis or tennis elbow, causes significant pain and disability in the upper extremity. Conservative approaches include using thermal and electrical agents. The aim of this study was to explore the effectiveness of shortwave diathermy on pain, function and grip strength of patients with chronic lateral epicondylitis. A randomized placebo-controlled design with concealed allocation, assessor blinding and intention-to-treat analysis was conducted. METHODS: Fifty patients suffering from lateral epicondylitis for more than 3 months, without any systemic diseases or history of other pathologies, were divided into two groups. In both groups, the patients were instructed to perform specific stretching and strengthening exercises. In addition, the patients in the experimental group, received 15â¯min of 40-60â¯W, continuous short wave diathermy while sham diathermy was applied for the control group. The primary outcome measure was pain and the secondary outcome measures were functional ability and pain free grip strength. Outcomes were assessed at the base line, after the 5th and the 10th session of treatment as well as after 3 months. RESULTS: Mixed ANOVA analysis showed significant improvement in both groups. Meanwhile, there was a significant interaction effect of time and group on all outcome measures implying the greater improvement in pain, function and grip strength in the group receiving real diathermy. CONCLUSIONS: Adding continuous short wave diathermy to a specific regimen of exercises, reduces pain and improves function in patients suffering from chronic lateral epicondylitis more than sham diathermy and exercise. TRIAL REGISTRATION: IRCT2016042321139N4.