One of the largest and most complex joints, the shoulder includes the clavicle (collarbone), scapula (shoulder blade), and humerus (upper-arm bone) and the ligaments and muscles that connect those bones. The humerus and the scapula fit together like a ball and socket. The shoulder allows a wide range of arm movement but also has to be stable enough that you can lift and pull heavy objects. Our shoulders are naturally somewhat unstable and prone to strain or posture related problems.
Shoulder pain is often felt in the upper arm. It is also closely related and often involved in neck and upper back problems.
Frozen Shoulder (Adhesive Capsulitis), Labral Tear, Rotator Cuff Tear/Strain, Shoulder Dislocation, Treatment After Surgery, Bursitis, Tendonitis, instability, and general shoulder pain.