Shoulder kinematics impact subacromial proximities: a review of the literature

Abstract

Background: Alterations in glenohumeral and scapulothoracic kinematics have been theorized to contribute to rotator cuff pathology by impacting the magnitude of the subacromial space. Objective: The purpose of this review is to summarize what is currently known about the relationship between shoulder kinematics and subacromial proximities. Conclusions: A variety of methods have been used to quantify subacromial proximities including photographs, MR imaging, ultrasonography, and single-and bi-plane radiographs. Changes in glenohumeral and scapulothoracic kinematics are associated with changes in subacromial proximities. However, the magnitude and direction of a particular motion's impact on subacromial proximities often vary between studies, which likely reflects different methodologies and subject populations. Glenohumeral elevation angle has been consistently found to impact subacromial proximities. Plane of humeral elevation also impacts subacromial proximities but to a lesser degree than the elevation angle. The impact of decreased scapulothoracic upward rotation on subacromial proximities is not absolute, but instead depends on the angle of humerothoracic elevation. The effects of scapular dyskinesis and humeral and scapular axial rotations on subacromial proximities are less clear. Future research is needed to further investigate the relationship between kinematics and subacromial proximities using more homogenous groups, determine the extent to which compression and other factors contribute to rotator cuff pathology, and develop accurate and reliable clinical measures of shoulder motion.

Humeral elevation workspace during daily life of adults with spinal cord injury who use a manual wheelchair compared to age and sex matched able-bodied controls

“…Both individuals with SCI and controls spent the majority of their day (~80%) in elevation angles between 0 and 60°. However, individuals with SCI spent significantly more time in humeral elevations previously found to be associated with supraspinatus tendon compression (30–60°) than controls [ 27 , 50 , 51 ]. There was no evidence of the effect of injury level, years of MWC use, age, or sex on the humeral elevation workspace for individuals with SCI.…”

“…Due to the increased prevalence of shoulder pain and pathology in MWC users compared to able-bodied controls [ 11 ] and the potential role that humeral elevation has on shoulder tendon compression [ 15 ], we hypothesized that MWC users would utilize a different humeral elevation workspace than able-bodied adults. Specifically, we hypothesized individuals with SCI would spend a higher percentage of time at elevation angles previously associated with tendon compression risk [ 27 ]. Understanding the humeral elevation workspace of individuals with SCI may contribute to understanding why increased levels of shoulder pain and pathology occur for this population.…”

The Relationship between Scapular Upward Rotation and Shoulder Internal and External Rotation Isokinetic Strength in Professional Baseball Pitchers

“…Decreased SUR at an HEA of 90° might be related to the development of pain through mechanical compression of the rotator cuff [ 33 ]. Meanwhile, an increase in SUR in accordance with HEAs could be important for avoiding subacromial impingement [ 34 ]. In general, it has been known that the rotator cuff muscles primarily stabilize the scapula-humerus joint, but also contribute significantly to movement, such as IR and ER [ 35 ].…”

“…In baseball players, the scapula must protract and rotate in the upward direction when the humerus is adducted horizontally during arm elevation in the arm cocking phase [ 54 ]. However, studies on muscle activation according to SUR mention that patients with symptomatic rotator cuff tears showed less SUR and higher activity of the levator scapulae on elevating the arm by 90° [ 34 ]. The minimum distance between the coracoacromial arch and rotator cuff insertion was observed to occur near or below an HEA of 90° [ 55 ].…”

Subakromiyal ağrı sendromunda yumuşak doku esnekliği ile akromiyohumeral mesafe arasındaki ilişkinin araştırılması

“…14,15 Yapılan çalışmalarda SAS'lu hastalarda görülen omuz çevresi yumuşak doku esneklik kaybının skapular pozisyonda değişime ve postüral asimetriye neden olabileceği bildirilmektedir. 9,13,16,17 Omuz Normal Eklem Hareket Açıklığı Değerlendirmesi: Bilateral omuz fleksiyon, abduksiyon, eksternal ve internal rotasyon eklem hareket açıklığı ölçümü sırtüstü yatış pozisyonunda standart gonyometre kullanılarak pasif olarak yapıldı ve elde edilen değer derece cinsinden kaydedildi. Her bir hareket için ardışık 3 ölçüm alındı ve ortalama değer kaydedildi.…”