Desempenho muscular em indivíduos com e sem lesão do manguito rotador em tarefas de alcance e preensão

Abstract

Introduction: The glenohumeral joint plays a fundamental role in the execution of upper limb tasks, including the manipulation of objects by the human hand. The rotator cuff muscles are important active stabilizing elements in the execution of shoulder movements. Changes in the integrity of the muscles and tendons of the rotator cuff compromise shoulder movements with repercussions on hand function. Objectives: To evaluate the muscle recruitment pattern in the upper limb and the handgrip strength of individuals with and without shoulder rotator cuff injuries while performing reach and grip tasks. Methodology: Eighteen participants (age: 59.39 ± 8.19 years) were divided into three groups (control group, CG; group with no pain and rotator cuff injury, SDCL; and group with pain and rotator cuff injury, CDCL). All performed specific tasks and movements with both limbs, but in a randomized manner, as well as performing handgrip tasks in a standardized position. Surface electromyographic recordings were obtained in the upper trapezius, deltoid and biceps brachii muscles on the right and left sides during the execution of the tasks. Dynamometry data were obtained regarding the handgrip strength of the limb. Results: We did not find significant differences in the analysis of the activation of the upper trapezius, anterior deltoid and biceps brachii muscles during the execution of the tasks performed, namely - 2, 7 and 17 of the Wolf motor test. There was no statistical difference in the dynamometry measurement during the maximum handgrip task between the CG, SDCL and CDC groups. The data did not differ between the right and left sides. Conclusion: The study of the population investigated here did not reveal an influence on the pattern of muscle recruitment nor on handgrip strength according to the presence of rotator cuff injury and pain. Future studies may contribute to a more detailed description of shoulder muscle activation patterns in specific postures in a larger population.