Shoulder pain is a very common complaint responsible for millions of doctor visits each year. After back pain, it’s the second most common musculoskeletal complaint. Shoulder pain can result from literally hundreds of causes. Nerves are ultimately responsible for signaling pain, and the shoulder is surrounded by a rich network of nerves. Many are on their way to other sites in the body. Sometimes pain or injury in one area of the body is actually felt in another area. This is sometimes called referred pain. Successful treatment of shoulder pain really depends on identifying the cause of your shoulder.
Pain. In other words, an accurate diagnosis is the most important thing. Pain in this anterior chest area certainly can have referred pain from heart, lungs, or GI tract. Certainly cervical issues can be referred to this region as well. Typically, shoulder mediated pain does not refer to the anterior chest wall itself. Once we take away the pectoralis major tendon we also see the pectoralis minor and also see a significant number of nerves that are coming out of the cervical spine traveling behind the collar bone or clavicle on their way down the arm along the chest wall.
So it’s easy to imagine that pain in this region can result from referred pain from this rich network of nerves traveling behind the coracoid and pectoralis minor. Tightness of the pectoralis minor can also result in shoulder impingement. Typically, impingement pain is in this anterior anterolateral area. But the most common cause of pain in this region in many patients’ and physicians’ perception is the rotator cuff. Here we see the anterolateral area after the deltoid has been taken away, and we see the supraspinatus portion of the rotator cuff.
Shoulder Pain and Common Shoulder Problems
The CA ligament which stands for coracoacromial ligament, and this is a very important ligament as it completes the circle of the shoulder. This ligament is also not apparent on an Xray, and when bone ossification of this ligament occurs, this typically is called a spur because that point appears to be out in space digging into the rotator cuff which actually is a misnomer. Anterior shoulder pain where the biceps goes for a lot of people means biceps mediated pain, but again this is a very nonspecific area of pain and a lot of different causes can be referred here.
We can see a significant number of nerves passing by the area of the biceps on their way down the arm. And again, cervically mediated pain can be referred here, pain from other chest wall abnormalities, and certainly shoulder pathology itself can also be referred as anterior shoulder pain. The other part that can result in interior shoulder pain is a problem with the subscapularis which is the hidden part of the rotator cuff because it’s so often missed. Occult shoulder instability can also present primarily as anterior shoulder pain. As we move on to the posterior aspect of the rotator cuff here we see the infraspinatus.
And the teres minor, and typically, pathology here will result in posterior shoulder pain. Again, posterior shoulder pain has a lot of different causes, tightness, muscular strain, referred pain again from the cervical spine, also referred pain in this region can come from a pinched nerve in the shoulder like the suprascapular nerve. Again we see a significant number of deeper muscles connecting the shoulder girdle to the remainder of the skeleton and a strain or sprain in any of these can result in pain in the upper back and posterior shoulder. So it’s important to see that the shoulder.
Girdle fits within the overall skeletal system and you can imagine if there’s abnormal curvature of the thoracic spine that might make the shoulder blade tilt forward further creating impingement and shoulder pain. So it’s important to evaluate all of these things and any evaluation of the shoulder includes movement of the shoulder blade and overall mobility and balance of the muscles anterior and posterior. We come back to the CA ligament which I mentioned is a very important structure because it completes the circle and also limits anterior superior migration of the humeral head.