The shoulder is comprised of several joints that combine with tendons and muscles to allow a wide range of motion to the arm. Due to the shoulder's anatomy, most shoulder problems involve the soft tissues, muscles, ligaments and tendons -
not the bones.

It is a ball and socket joint with a very shallow socket which allows a large range of motion but at the cost of the tendency to dislocated if the ligaments become injured.

The rotator cuff tendons, especially the supraspinatus tendon, do not have much room under the acromion of the scapula (shoulder blade). This leads frequently to tendinitis, tears of the rotator cuff and inflammation of the subacromial bursa (bursitis).

Another common condition which causes pain and deterioration of the shoulder is arthritis. Some rare problems include tumors, infection and nerve related conditions.