Scapular kinematics and pathoanatomic alterations of the supraspinatus and infraspinatus muscles: comparison between sides in individuals with unilateral shoulder pain

• Grant number: 18/09980-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: April 01, 2019
• End date: December 31, 2019
• Field of knowledge: Health Sciences - Physiotherapy and Occupational Therapy
• Principal Investigator: Paula Rezende Camargo
• Grantee: Beatriz Mayumi Dias Tazawa
• Host Institution: Centro de Ciências Biológicas e da Saúde (CCBS). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

Alterations of scapular kinematics are commonly observed on the symptomatic side of individuals with unilateral shoulder pain. Some studies have compared the kinematics between symptomatic and asymptomatic sides, however, results are still inconclusive. There are also few studies evaluating on both sides the presence of structural changes in the rotator cuff tendons in individuals with unilateral symptoms.Objectives: The primary objective of this study will be to compare the scapular kinematics during elevation and depression of the arm in the sagittal plane between symptomatic and asymptomatic sides in individuals with unilateral shoulder pain. The secondary objective will be to describe the frequency of pathoanatomic changes in the supraspinatus and infraspinatus tendons on both sides.Methods: Individuals with unilateral shoulder pain will be recruited to participate in this study. Individuals must have an arm flexion range of at least 150° as measured by a digital inclinometer. 3-D evaluation of the scapular kinematics will be performed using the Flock of Birds mini-bird® electromagnetic tracking system. All participants will undergo a magnetic resonance imaging protocol to assess the frequency of pathoanatomic changes in the supraspinatus and infraspinatus tendons. Data normality will be verified through the Kolmogorov-Smirnov test. Scapular kinematics data during arm elevation and depression will be analyzed by 2-way ANOVA to verify the interaction between side (symptomatic and asymptomatic) and angle (30º, 60º, 90º, 120º). If no interaction is observed, main effect will be analyzed. Bonferroni post-hoc test will be used when interaction is observed. Frequency of pathoanatomic findings between the two sides will be compared with the Chi-square test for independence. A p-value of 0.05 will be considered as statistically significant.