Effects of Photobiomodulation Therapy Combined With Static Magnetic Field in Patients With Lateral Epicondylitis

Evaluation of the Effects of Photobiomodulation Therapy Combined With Static Magnetic Field (PBMT-sMF) on Temporary Pain Relief in Patients With Lateral Epicondylitis

Lateral epicondylitis (LE) is one of the most frequently encountered lesions affecting the upper extremity and is the most common cause of elbow pain in adults. It occurs on the lateral side of the elbow where the common extensors originate from the lateral epicondyle. LE can be considered an overuse injury which occurs on the lateral side of the elbow in the extensor tendons with repetitive micro-trauma. The clinical presentation of LE involves a painful or burning sensation over the humeral insertion of the common extensor tendons. Despite the high incidence of LE, optimal treatment has not been established. Treatment options include therapeutic exercise, bracing, shock wave or ultrasound therapy , but many of them lack sufficient evidence of beneficial effects. Photobiomodulation therapy (PBMT) alone or combined with static magnetic field (PBMT-sMF) has been shown to stimulate tendon healing, this suggests that therapy using laser or light-emitting diodes (LEDs) is efficacious for the symptoms associated with epicondylitis. According to the favorable results of PBMT-sMF in tendons repair processes, this type of therapy can be used as a therapeutic tool for management in epicondylitis, therefore, more investigations are necessary to establish the ideal parameters. Therefore, the aim of this project is to investigate the effects of PBMT-sMF, in the appropriate parameters, on degree of pain and quality of life of patients with lateral epicondylitis.

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:

1. 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.
2. The secondary outcomes that are continuous variables will be analyzed through parametric analysis using ANCOVA. Statistical significance will be set at p<0.05.
3. 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.

Inclusion Criteria:

• Patients with a history of pain around the lateral epicondyle for at least 1 month;
• Self-reported Degree of Pain rating on the 0-100 VAS pain scale for the lateral epicondyle region is 50 or greater;
• Tenderness localized to the epicondyle and anterodistal region of the epicondyle with palpation;
• 2 of 4 positive results of provocative tests comprising of Maudsley's, Cozen's, Thomsen and Mill's tests;
• Aged between 18 and 50 years;
• Both genders;
• Patients fluent in Portuguese.

Exclusion Criteria:

• hemophilia or any type of blood clotting disorder;
• chronic immune impairment neoplasia;
• cancer or treatment for cancer in the past 6 months, including tumors of the spinal cord;
• diabetes Type 1;
• significant heart conditions including CHF and implantable heart devices such as a pacemaker;
• current, active chronic pain disease: chronic fatigue syndrome, fibromyalgia, endometriosis, inflammatory bowel disease, interstitial cystitis diabetic neuropathic pain;
• neurologic deficits;
• cervical radiculopathy;
• peripheral nerve disease;
• rheumatoid arthritis;
• shoulder disease;
• radial tunnel syndrome;
• previous surgery of the affected upper extremities;
• congenital or acquired bony deformity in the ipsilateral upper extremity;
• bilateral epicondylosis;
• secondary orthopedic problems;
• the initiation of opioid analgesia or corticosteroid or analgesic injection interventions within the previous 6 months;
• local corticosteroids and/or botulinum toxin (Botox®) injection for Lateral Epicondyle pain relief within the prior 30 days;
• medical tx; such as chiropractic care and acupuncture within last 30 days;
• physical therapy intervention on the upper extremity in the previous year;
• active infection, wound, or other external trauma to the areas to be treated with the laser;
• medical, physical, or other contraindications for, or sensitivity to, light therapy;
• serious mental health illness such as dementia or schizophrenia; psychiatric hospitalization in past two years;
• pregnant, breast feeding, or planning pregnancy prior to the end of study participation.