The “rotator cuff” is a set of four muscles around the glenohumeral joint including the supraspinatus, infraspinatus, subscapularis, and teres minor (see figure). These muscles all originate from the scapula, insert at various points on the humerus, and serve multiple coordinated functions including abduction, adduction internal rotation, external rotation, and stabilization. Each muscle is considered …
In part 2 of our shoulder series we discussed the topic of “shoulder impingement”, which is commonly understood as the mechanical compression of the tissues beneath the acromion process, resulting in pain or dysfunction — better known as external impingement. We described the biomechanical theory behind this diagnosis, and examined the available research evidence on …
In the first article of this series we discussed the concept of “normal” or “abnormal” scapular movement (i.e., scapular dyskinesis), which is the pathomechanical foundation upon which other shoulder-related diagnoses and narratives are built. “Shoulder impingement” is one of these ideas that is commonly discussed in the coaching, rehab, and orthopedic worlds. The narrative describes …
