Shoulder pain can be the result of injury or inflammation of the rotator cuff. These include subacromial impingement, where the gap between the rotator cuff and the acromion decreases and as a result, when you raise your arm, the acromion starts impinging the tendon and bursa, leading to pain and inflammation. Shoulder pain may also be caused by bursitis, where the bursa gets inflamed which leads to swelling. As fluid gathers in the swollen area, it intensifies the pain.
Shoulder pain can sometimes be a symptom of an ailment, such as chest pain and nausea. In that case, if you have a history of any diseases which can cause shoulder pain, make sure you consult your physician as soon as you experience any discomfort in the shoulder.
The most common cause of shoulder pain is sudden trauma. If you have been in an accident and hurt your shoulder, you may experience shoulder pain. People with frozen shoulder can also suffer from regular episodes of pain. Arthritis and bursitis are other causes of shoulder pain.