Objective: Tennis elbow disorder causes pain and tenderness in the lateral section of the elbow and it has also been found reducing the grip force of the individual. The objective of the current research paper is a comparative evaluation of the effect of high-power and low power laser therapy on the pain, tenderness and grip force of the patients with such a syndrome. Study Method: Thirty individuals previously diagnosed with tennis elbow disorder participated in the study after being subjected to the study inclusion and exclusion criteria. The variables studied herein were the pain intensity, tenderness and the grip force of the participants. The aforementioned variables were examined based on visual pain scale, algometer and dynamometer before and after the treatment. The study subjects were randomly assigned to two treatment groups: 1) group one, which was subjected to the high-power laser therapy and common treatments (n=15) and 2); group two, which was subjected to low-power laser therapy and common treatments. The treatments were administered in ten sessions, six days in a week. Evaluations were carried out at the beginning, and the end of the treatment sessions by a therapist. To determine the changes in the variables in both of the treatment groups after the termination of the treatment sessions, paired t-test was used, and independent t-test was applied to compare the two foresaid methods. Findings: The results of the study indicated that the effect of the high-power laser therapy along with the common treatments were statistically significant in the reduction of pain, tenderness and the increase in the grip force of the patients (P<0.05); also, the use of low-power laser therapy along with common treatments was found creating significant differences (P<0.05), but a comparison of the two treatment groups was not suggestive of any significant differences between them in terms of any of the variables (P>0.05).
Conclusion: Both types of low-power and high-power laser therapy along with common physiotherapy treatments were effective on the reduction of pain and tenderness and the increase in the grip force of the patients with tennis elbow; and they did not show any significant differences.