Frozen shoulder (i.e. adhesive capsulitis) is a condition which affects your ability to move the shoulder. It usually occurs on one side, but it can affect the other shoulder for every one in five people. The medical term, adhesive capsulitis, describes the changes to the capsule around the shoulder joint; adhesive meaning sticky and capsulitis meaning inflammation of the joint capsule. Since the capsule has become inflamed and 'sticky', it makes the joint stiff and difficult to move. This is not the same as arthritis and other joints in the body are usually unaffected.
Frozen shoulder is uncommon among young people and is usually seen in those around the 40 to 70 year age range. There is a higher occurrence of this condition in women and those affected by diabetes.