Cinemática escapular : confiabilidade e efeitos pré e pós uma manipulação torácica em sujeitos com e sem sintomas de impacto - um estudo controlado randomizado

Abstract

Background: There is a lack of studies that evaluated within day and between day reliabilities of 3-D scapular kinematics during elevation and lowering of the arm in different shoulder conditions, as well as studies about low-amplitude and high-velocity thoracic spine manipulation (TSM) effects on scapular kinematics in subjects with shoulder dysfunctions. Objective: To establish within day and between day reliability of scapular motion during elevation and lowering of the arm and at rest position and to evaluate the immediate effects of a TSM on pain and scapular kinematics during elevation and lowering of the arm, both in subjects with and without shoulder impingement syndrome (SIS). Methods: Kinematic data were collected using Flock of Birds® electromagnetic device. Subjects were divided in 2 groups: control and impingement. For reliability kinematic data were collected during elevation and lowering of the arm and at rest position on 2 different occasions separated by 3 to 5 days. Forty-nine subjects were tested for within day reliability. Forty-three subjects were reassessed for between day reliability. For kinematic evaluation pre- and ppost-manipulation, scapular kinematics was collected during elevation and lowering of the arm before and immediately after the intervention. Numeric pain rating scale was used to assess shoulder pain during arm movement at pre- and post- intervention. Fifty subjects (31.76 ± 10.91 years) with SIS and 47 subjects (25.76 ± 5.01 years) asymptomatic for shoulder dysfunctions were randomly assigned to one of the groups: manipulation or sham. Results: There was very good within day reliability for assessing scapular internal and upward rotations and tilt from both groups during elevation and lowering of the arm (ICC=0.92-0.99). In general, there was good between day reliability for assessing scapular motion during elevation and lowering of the arm from both groups (ICC=0.54-0.88). There was also good and very good between day reliability for assessing scapular rest position in both groups (ICC=0.66-0.95). Study 2: Subjects with SIS experienced reduced shoulder pain (from 3.29 to 2.45, p<0.01) during arm movement immediately after TSM. Subjects with and without SIS who received TSM and asymptomatic subjects who received sham intervention showed significant increase in scapular upward rotation at post-intervention. Increase in scapular anterior tilt at postmanipulation was also observed in asymptomatic subjects who received TSM. Conclusion: Flock of Birds® electromagnetic tracking system is a reliable device for measuring 3-D scapular motion during elevation and lowering of the arm and at rest position in subjects with and without impingement symptoms over time. TSM is associated with improved shoulder pain and scapular upward rotation in subjects with SIS. Although with questionable clinical relevance, TSM may not be immediately favorable to scapular tilt in asymptomatic subjects.