Scapular Kinematics and Subacromial-Impingement Syndrome: A Meta-Analysis

Abstract

Context:The literature does not present a consistent pattern of altered scapular kinematics in patients with shoulder-impingement syndrome (SIS). Objectives: To perform meta-analyses of published comparative studies to determine the consistent differences in scapular kinematics between subjects with SIS and controls. In addition, the purpose was to analyze factors of the data-collection methods to explain the inconsistencies in reported kinematics. The results of this study will help guide future research and enable our understanding of the relationship between scapular kinematics and SIS. Evidence Acquisition: A search identified 65 studies; 9 papers met inclusion criteria. Sample sizes, means, and SDs of 5 scapular-kinematic variables were extracted or obtained from each paper's lead author. Standard difference in the mean between SIS and controls was calculated. Moderator variables were plane of arm elevation, level of arm elevation (ARM) and population (POP). Evidence Synthesis: Overall, the SIS group had less scapular upward rotation (UR) and external rotation (ER) and greater clavicular elevation (ELE) and retraction (RET) but no differences in scapular posterior tilt (PT). In the frontal plane, SIS subjects showed greater PT and ER, and in the scapular plane, less UR and ER and greater ELE and RET. There was also greater ELE and RET in the sagittal plane. There was less UR at the low ARM and greater ELE and RET at the high ARM with SIS. Athletes and overhead workers showed less UR, while athletes showed greater PT and workers showed less PT and ER. The general population with SIS had greater ELE and RET only. Conclusions: Subjects with SIS demonstrated altered scapular kinematics, and these differences are influenced by the plane, ARM, and POP. Athletes and overhead workers have a different pattern of scapular kinematics than the general population. The scapular plane is most likely to demonstrate altered kinematics. These factors should be considered when designing futures studies to assess the impact of altered kinematics in patients with SIS.

Measurement of Dynamic Scapular Kinematics Using an Acromion Marker Cluster to Minimize Skin Movement Artifact

“…Objective, quantitative measurement of scapular kinematics can provide an assessment of abnormal movement patterns associated with shoulder dysfunction 1 , such as reduced upward rotation and posterior tilt during arm elevation observed in shoulder impingement [2][3][4][5][6][7][8] . Measurement of scapular kinematics, however, is difficult due to the bone's deep position and gliding nature beneath the skin surface 1 .…”

Scapular dyskinesis was not associated with pain and function in male adolescent athletes

“…Results indicate that for a population of adolescent athletes with an amateur sports level, the dyskinesis prevalence is high; however, it is not associated with pain and does not seem to affect measures of upper limb function. Although some studies support the relationship between pain/ lesion and scapular dyskinesis 2,[7][8][9][10][11] , more than half of the current sample (56.7%) presented changes in scapular movement without, however, being associated with shoulder pain. The results of this study corroborate those of Oliveira et al 28 who analyzed amateur male athletes with shoulder injury syndrome and observed no association between dyskinesis and shoulder pain.…”

“…Specifically, the modification in the scapula positioning, called scapular dyskinesis, has been studied because it presents possible relations with the presence of pain and shoulder injuries in athletes 2,[6][7][8] . Most of the studies state the relation between shoulder pain/ injury and scapular dyskinesis 2,7,[9][10][11] . Such research ensures that ORIGINAL ARTICLE DOI 10.5935/2595-0118.20180009 changes in scapular kinematics may result in structural and functional changes in the glenohumeral and acromioclavicular joints, decreased subacromial space, changes in the scapular muscles activation and, consequently, leading to dysfunctions such as shoulder-rotator cuff syndrome, rotator cuff tendinopathies, glenohumeral instability, and other conditions.…”

Clinical assessment of subacromial shoulder impingement – Which factors differ from the asymptomatic population?

“…Borstad & Ludewig, 2002;P.M. Ludewig & Cook, 2000;Timmons et al, 2012) and dysfunction or weakness of the rotator cuff musculature (Brox et al, 1999;N. Hanchard et al, 2004;Leroux et al, 1994;Michener et al, 2003;Reddy, Mohr, Pink, & Jobe, 2000;Sorohan & Mc Creesh, 2009;Warner, Micheli, Arslanian, Kennedy, & Kennedy, 1990).…”