EMG Muscle Activity of Middle Trapezius and Lower Trapezius during Arm Elevation in Subjects with and without Shoulder Impingement: A Systematic Review

有無肩關節夾擠者在手上抬動作中斜方肌與下斜方肌肌電活化表現：系統性文獻回顧

康富傑(Fu-Jie Kang) ； 林昆瑩(Kun-Ying Lin) ； 林居正(Jiu-Jenq Lin)

《物理治療》 42卷4期 (2017/12) Pp. 363-364

https://doi.org/10.6215/FJPT.2017.74.P34

摘要

Background and Purpose: During arm elevation, a complex scapular movement is needed to create a stable base for the glenohumeral joint. In this point of view, scapular muscles, such as upper trapezius (UT), middle trapezius (MT), lower trapezius (LT), and serratus anterior (SA), need to provide stability and mobility in well-coordinated to facilitate adequate scapulaohumeral movement. Several studies indicated that people with shoulder impingement have deficit in scapular muscles activity. However, conflicting evidence exists for the MT and LT. Impaired LT and MT activity have been reported by some, whereas others have reported no differences in LT and MT activity. Thus, the aim of the present review was to retrieve and quantify outcomes from relevant articles and to compare the surface electromyographic (EMG) data about MT and LT in participants with and without shoulder impingement during arm elevation task. Methods: The following database was searched including the PubMed from inception to December 2016 by using relevant keywords ＂with and without shoulder impingement, arm elevation task, MT and LT EMG＂. Studies that didn't focus on shoulder impingement were excluded. Results: Based on the database search, 19 articles were selected. Following the selection criteria, shoulder impingement, arm elevation task and EMG data, five out of 19 articles met the criteria. Based on the 5 studies, 2 studies investigating MT muscle activity and 5 studies examing LT muscle activity, 101 people with shoulder impingement and 96 controls were analyzed. We found LT muscle activity deficit in the subjects with shoulder impingement as compared to the controls during arm elevation among the 5 studies. However, there was no difference for MT muscle activity among the 2 studies. Conclusion: Following this review, deficient of LT muscle activity was common in patients with shoulder impingement. Clinical Relevance: In this point of view, it should be a regular practice to evaluate and train LT muscle activity in shoulder impingement patients.