Analysis of the Effect of Neuromuscular Electro-stimulation on the Performance of Isometric Rotator Cuff Strength.

Introduction: Shoulder disorders are a common musculoskeletal problem causing pain and functional loss in different populations. Tendinopathies are a group of pathologies commonly diagnosed in patients with shoulder pain. Weakness of the rotator cuff musculature has already been documented in other studies, evidence in the literature suggests that patients with tendinopathies demonstrate decreased muscle activation, this is caused by pain, changes in nervous system processing and apparently also by structural processes that occur in the tendon .Treatment often involves resistance, isometric exercises aimed at altering pain and restoring function. Some studies have been investigating the use of ENMS (neuromuscular electrical stimulation) in patients undergoing surgical procedures on the shoulder, other studies have also investigated its use in tendinopathies of the lower limbs, as an effective way to decrease inhibition. Objective: The main objective of this study will be to analyze the muscle strength of internal and external rotation of symptomatic shoulders compared to asymptomatic ones when exposed to neuromuscular electrostimulation, associating muscle strength with joint function. Methodology: This will be a cross-sectional study. An expected total of 48 subjects will be divided into two groups, n=24 with tendinopathy of the rotator cuff, confirmed by clinical diagnosis and nuclear magnetic resonance imaging, the other group being healthy individuals, with no history of shoulder pain. These individuals will be evaluated by a first evaluator who will perform the eligibility of the subjects and collect the initial information, the second evaluator will perform the isometric strength evaluation with a manual dynamometer. Two batteries of tests will be performed in both groups, a conventional assessment of isometric strength and the other subject will be submitted to neuromuscular electrostimulation. These strength values in Kgf were normalized for each individual, being divided by the body mass index (BMI) and multiplied by 100, as already performed in previous studies. Expected results: The initial hypothesis is that patients who present with the studied condition when submitted to the strength test with muscular electrostimulation will demonstrate greater isometric strength than when they were tested without the device.