The Influences of Subscapularis Lesion on Ultrasonography and Kinematics in Patients With Shoulder Impingement

Subacromial and subcoracoid impingement have been categorized as external impingement, one type of shoulder impingement syndrome (SIS). Differentiation between subacromial impingement and subcoracoid impingement are important in determining the treatment target. The thickness of the coracohumeral ligament (CHL) may affect coracohumeral distance (CHD), which has been suggested as a possible factor in developing subcoracoid impingement with subscapularis (SSC) lesion. Evidence that indicates the existence of abnormal SSC, CHL thickness and CHD in people with SIS is limited. The purposes of the study were (1) to evaluate the correlations between CHL thickness and CHD by using ultrasonography in people with SIS with and without SSC lesion, (2) to examine the difference in SSC/CHL thickness and CHD between people with SIS with and without SSC lesion.