Tendonitis is an inflammatory condition of a tendon, usually resulting from a strain.  Although acute tendonitis usually heals within a few days to two weeks, it may become chronic.  In such cases, calcium salts typically deposit along the tendon fibers. The tendons most commonly affected are those connected to the back of the ankle, the elbow, the shoulder, the thumb, the upper knee cap, and the inside of the foot....

Temporomandibular joint disorder, or TMJ, produces pain in the muscles and joints of the jaw that sometimes radiates to the face, neck, and shoulder.  There may also be difficulty opening the mouth all the way.  Clicking, grinding, and popping noises may occur during chewing and movement of the joint.  Other common signs of TMJ are toothaches, facial pain, neck stiffness, and ringing in the ears.  These are usually minor to moderate annoyances that will go away when the condition is corrected....