Most of the shoulder joint problems start as a complaint of pain. Pain is the princeps syntom of shoulder pathology so as in the rest of the body. Also, the pain is the cause of a visit to a medical specialist.
The study of this syntom in his different aspects, like presentation, duration, etc, give us an opportunity of knowing its more probably source and what will be the solutions to its erradication.
There are other important aspects to consider in a subject with pain on the shoulder region: age, is an important factor which we have to study becaouse of its relevance. Most of the shoulder problemas in paitents older than 50 years old use to suffer from degenerative processes, but in younger individuals we should suspect a mechanical or inflamatory problems as a cause of pain. Secondly, working phisical activity is a determining factor at the moment of instauration of symptoms. So individuals with upper part limb hard demanding activities like electricians, building workers, house cleaning, suffer with more frequency in a different moment of their lives problems related to the shoulder function. It is important to discharge those possible causes of shoulder pain which source comes from another place like as an example:

a, Toracic outlet syndrome
b, Cervical root pathology
c, Lung pancoast tumor
d, Transient anxiety syndrome
e, Others...

Study of pain and its characteristics is the key to distinguish between local pain and referred pain..

From all the way of presentation syntoms, pain at night is the most common sign of subacromial estenosis. Going to bed is an activity in which we reduce our physical activity ang grow up our sensititvity to any possible complaints that could not have been caused problems during the day. In this situation the patients can not sleep, and may have also a problem of insomnio.

Frequently the pain starts gradually in the vast majority of cases (80%), due to a mechanical problem which progressively damage the soft tissues. Others, pain come out suddenly after an effort of tendon tensioning , and also it has been seen an spontaneously breakage after a long period of injuring the tendons which collapsed totally.