Progression of rotator cuff disease and biceps tendinopathy.

Shoulder impingement is a major contributor to either the development or progression of rotator cuff disease and biceps tendinopathy. In asymptomatic individuals, elevation in any plane includes scapulothoracic upward rotation, posterior tilting and internal or external rotation; motions, which are the result of complex, coupled interactions between SC and AC joints. Taking these interactions and data derived from modeling studies into account, the primary role of the upper trapezius seems to be to retract the clavicle at the SC joint. The middle and lower trapezius and serratus anterior produce scapulothoracic upward rotation relative to the clavicle; additionally the serratus anterior contributes to posterior tilting. It is important to appreciate biomechanical evidence, such as AC and SC joint interactions, muscle function and possible mechanisms of abnormal movement patterns when rehabilitating patients presenting with shoulder pain in order to select specific interventions > from Ludewig et al.; Manual Therapy 16 (2011) 33-39. All rights reserved to Elsevier.