Scapular Stabilization for Shoulder Pain: Putting the Cart Before the Horse?

Abstract

Observational evaluation of arm elevation is a routine part of the examination of patients with shoulder pain and dysfunction. However, the interdependency of the glenohumeral and scapulothoracic joints during arm elevation presents a challenge for clinicians when attempting to characterize movement impairments and underlying causes. Given that identification of movement impairments related to the scapulothoracic joint (i.e. scapular winging or excessive scapular elevation) are more easily observed compared to movement faults at the glenohumeral joint (i.e. superior or anterior translation of the humeral head) an inherent bias may exist in which clinicians prioritize movement impairments and associated physical impairments at the scapulothoracic joint in developing a treatment plan. Interpreting the cause(s) of abnormal scapulothoracic motion without considering the potential influence of the glenohumeral joint (and vice-versa) may lead to faulty clinical reasoning when developing a plan of care. The purpose of this clinical commentary is to highlight the potential impact of faulty glenohumeral joint mechanics as being contributory to scapulothoracic joint kinematics. We first review the normal kinematics and muscular actions associated with typical arm elevation and then discuss how impairments at the glenohumeral joint may be contributory to faulty scapulothoracic motion. Specifically, we address movement faults characterized by excessive motion of the scapula.

Level of evidence: 5.