In analyzing this series of cases there are certain factors that stand out:
1. There are three different types of cases classified under subdeltoid bursitis.
2. It is not a condition of youth, but of middle and old age. There are no cases in which the patients were under thirty years of age, and the only group in which there is an appreciable number of patients between the ages of thirty and forty is the acute fulminating type.
3. There is no evidence that there is an element of focal infection, as is so commonly thought. Therefore, the term periarthritis is misleading.
4. In order to prevent the long-drawn-out treatment that is sometimes necessary in these cases, one should have a clear picture in mind as to what is going on and what the results should be. Much of the treatment that is not logical or necessary could then be prevented.