The shoulder is a complex ball and socket joint that is made up of the humerus (arm bone), the scapula (shoulder blade) and the clavicle (collar bone). The shoulder is supported by many ligaments and muscular attachments that help to move it. An extremely mobile joint, the shoulder allows people to reach and move in many directions.

However, the shoulder is not a very stable type of joint and tends to be easily injured.  Shoulder pain can arise from problems with instability or impingement of the soft tissue or bony structure. The shoulder can be injured by performing manual labor, playing sports, or very often by repetitive movements especially with athletes performing overhead movements.  Pain and discomfort may be temporary or it may continue and require medical diagnosis and treatment.