Treatment of Lateral Epicondilar Elbow Tendinosis by infiltration of Platelet-Rich Plasma (PRP): a triple-blind, prospective, randomized and controlled study (part I)

Abstract

Lateral Epicondilar Elbow Tendinosis (LEET) is a disease that mainly affects workers who perform repetitive movements in excess, with the wrist, fingers and/or hands. It is an entity that culminates in quite disabling motor impairment, intensive pain and social security clearances. Treatment includes physiotherapy, immobilizations and corticosteroids infiltrations, with no consensus on the most effective method. Currently, Platelet Rich Plasma (PRP) has been successfully implemented in different types of musculoskeletal injuries. This is an autogenous source of growth factors, obtained by arrest and concentration of platelets by blood centrifugation. Its action influences the inflammation cascade by acting on infectious processes, osteogenesis and non-fibrotic healing of soft tissues, especially muscle. Given that the physical examination does not always reflect the actual functionality of the injured joint or the patient's degree of disability, there is a need for applying questionnaires or scales aiming at these goals. There are several rating scales available, such as "Patient-Rated Tennis Elbow Evaluation" (PRTEE) and "Disabilities of Arm, Shoulder and Hand" (DASH). The DASH is a questionnaire that measures the inability of the upper extremities from the patient's perspective, which is used to study the clinical outcome of musculoskeletal disorders, with high sensitivity and specificity. Primary Objectives: to analyze the effects of PRP local infiltrations in patients with LEET through a prospective, randomized, controlled trial. Secondary Objectives: To analyze the results from the DASH scale, comparing them to those obtained from the PRTEE. Patients and Methods: the sample size was determined previously to the start of the study, reaching a minimum of 20 individuals per group. All procedures were approved by the Research Ethics Committee, under no. 453/12. The patients selected for this study will be of both genders, ages higher than 18 years, who have had pain at the lateral epicondyle of the elbow for longer than six months. The final diagnosis of LEET and its evolution grade must be confirmed by an ultrasound test and by the positivity of two tests on physical examination. Patients that have already undergone previous treatments in the elbow region, those suffering from other diseases in the upper limb (as the Posterior Interosseous Nerve Syndrome and/or Carpal Tunnel Syndrome), patients with systemic diseases (such as diabetes, hypothyroidism, and/or rheumatoid arthritis), pregnancy, women under contraceptive pills treatment and those who refuse to sign the Term of Informed Consent, will be excluded. After the initial examination, patients will have their Protocol Assessment filled and will respond to Assessment Protocol and the DASH questionnaire. Afterward, patients will be randomized by drawing lots of opaque and sealed envelopes into three groups: group C (n = 20), underwent 3 ml of Neocaine 0,5% infiltration without epinephrine; group D (n = 20), underwent 3 ml of Dexamethasone infiltration, and group P (n = 20) underwent 3 ml of PRP infiltration. The localization of the infiltration point will be made by digital pressure and will be labeled with dermographic pen. After antisepsis process, a local anesthetic will be administrated (Neocaine 0,5%, 0,5 ml). The substances will be administered accordingly to the triple-blind protocol, by the same surgical staff. Patients will be evaluated every 60 days after infiltration, moments in which the DASH questionnaire will be answered again. Results will be analyzed after the end of the study, i.e. 180 days after the infiltration, comparing the results intra-study (DASH by itself) and inter-studies (DASH vs. PRTEE).(AU)