To achieve the proposed objective it will be performed a multi-center, randomized, triple-blinded, placebo-controlled trial, with voluntary patients with lateral epicondylitis. Fifty patients will be randomly allocated to two treatment groups: 1. Active PBMT-sMF (MR5® Prototype Device) or Placebo PBMT-sMF (MR5® Prototype Device). The patients will be treated by a blinded therapist.
The patients randomly allocated to the different groups will be subjected to treatment two times a week for three consecutive weeks, each procedure administration three to four days apart.
The study will contain five phases: 1) pre-procedure activities; 2) pre-procedure assessment phase; 3) procedure administration phase; 4) procedure administration phase measures; 5) post-procedure administration phase.
The outcomes measured will be: degree of pain, forearm pain and disability, grip strength, TNF-α levels, subject satisfaction with overall outcome rating, perceived group assignment and adverse events.
The outcomes will be obtained at the stabilization phase (pre-procedure activities), baseline (pre-procedure assessment phase), 24 hours after the end of the treatment (procedure administration phase measures), and 30 days after the end of the treatment (post-procedure administration phase).
Statistical analysis:
- The primary statistical method to analyze the primary endpoint will be Fisher's exact test to compare the proportion of success between the test (Active PBMT-sMF) and the control (Placebo PBMT-sMF) groups, considering that randomization has been diligently conducted and important covariates between the two groups are well balanced. Statistical significance will be set at p<0.05.
- The secondary outcomes that are continuous variables will be analyzed through parametric analysis using ANCOVA. Statistical significance will be set at p<0.05.
- For patient satisfaction, measured through a Likert Scale, the data will be reduced to the nominal level by combining all agree and disagree responses into two categories of "accept" and "reject". Differences in satisfaction with Study Outcome Ratings between procedure groups at both evaluated time-points, and any change between. The chi-square will be used after this transformation. Statistical significance will be set at p<0.05.