Shoulder subluxation is often confused with dislocation although they are not the same. A dislocation is one in which the humerus, the long bone of the upper arm, is temporarily dislodged from the socket. The key word here is temporarily, since the muscles and ligaments surrounding the joint will usually place the humerus right back where it should be. A subluxation is sometimes referred to as a partial separation.
A subluxation of the shoulder joint can, nevertheless, be a painful experience and if you are using your muscles strenuously, as would be the case in weightlifting or various sporting activities, your injury may be too painful to continue with your activities without a few days or even a few weeks of rest. After that, everything will hopefully return to normal.
To better understand what transpires when a subluxation occurs and what parts of the shoulder are involved, a brief look at the anatomy of the shoulder can be helpful.
The shoulder consists of three bones: the humerus or upper arm bone, the scapula or shoulder blade, and the clavicle or collarbone. The head of the humerus fits into a socket in the scapula called the glenoid cavity. This socket is surrounded by ligaments, which are strong connective tissues that stabilize the joint by keeping the humerus centered in the socket. These connective tissues are referred to as the shoulder capsule. Muscles and tendons also contribute to keeping the joint stable.
If the tissues that form the capsule become weakened, loose, or torn, they eventually reach a point where they become less and less able to keep the humerus properly positioned in the socket.
Subluxation vs Dislocation
A shoulder separation is different in that if the humerus has been displaced from the socket, it has to either be coaxed or forced back into the socket. The upper arm bone won’t simply return by its own accord. Consequently, a separation is generally taken more seriously than a subluxation since the former condition requires treatment, even if that treatment consists of nothing more than guiding the bone back to where it is supposed to be, while the latter condition tends to heal itself.
Subluxations can, however, lead to serious disorders. A separation usually occurs as a result of a fall or an injury to the shoulder. It is often a one-time event, although athletes will from time to time experience this type of injury more than once. A subluxation can be what you might call an insidious condition. It may have taken a hard hit to the shoulder to displace the humerus the first time, but it may not take quite so hard a blow to separate the bone from the socket the next time.
Even if the bone returns to the socket on its own again and again, over time the tissues that are there to stabilize the joint will become weaker. Consequently, a subluxation will for some people become a chronic problem. Even if the humerus returns to its rightful position each and every time there will still be pain involved and, over time, the joint will become less and less stable. By the time you finally visit a doctor or an orthopedic surgeon you may find that the doctor is able to subluxate your shoulder with about the same level of effort as it takes to open a door.
At some point in time, exercises that are done to strengthen the shoulder muscles can have the opposite effect. Those who work out with weights and have had subluxation problems in the past often have to be very careful about choosing the right exercise routine and, at times have to forgo certain exercises entirely, or as a minimum plan around those exercises that might cause a problem.
A Study of Common Causes
In 2007, a report was given to the National Collegiate Athletic Association by the American Orthopaedic Society for Sports Medicine (AOSSM). The report was based on a study done on more than 4,000 cadets attending the Military Academy at West Point. West Point was chosen since every cadet is required to participate in organized sports or physical activities such as boxing, rugby, gymnastics, or football. The cadets were, in essence, a captive group insofar as healthcare studies were concerned, making them an ideal study group. Both primary and recurrent injuries were recorded as soon as they occurred throughout the course of the study with particular attention being paid to dislocations and shoulder subluxations.
One of the unexpected results of the study was that the percentage of the injuries that were subluxations was much higher than had been anticipated. Not only did subluxations make up the majority of instability events, but approximately 50% of the cases resulted in injuries to tissues surrounding the shoulder joint, the injuries largely consisting of labral tears and humeral head lesions. What came out of these studies was a general consensus that over time subluxations could become a serious problem and the damage caused by these events was generally underappreciated in both the medical community and in medical literature.
Most of the incidents of subluxation in the aforementioned study came as a result of blows to the shoulder. Boxing was the number one cause. In this case it wasn’t only a blow to the shoulder that could cause a subluxation, throwing a punch and missing also puts a tremendous strain on the shoulder and on the tissues of the capsule.
Another cause can be simply that of a person’s anatomy. Not everyone is built the same. Some have looser ligaments in their shoulders than others and are therefore more susceptible to injuries. People who are double-jointed are more apt to experience subluxations or even dislocations than is the average person.
Treatment Options for Shoulder Subluxation
Initially, treatment usually involves nothing more than applying ice to reduce the swelling as well as the pain. This may have to be done several times a day for several days until it has healed. Over-the-counter medications can also be used to relieve the pain. It’s also advisable to rest the shoulder for several days. You don’t want to avoid using it completely or a case of frozen shoulder could develop. Wearing a sling for a good part of the day, but not all day, would make the most sense.
Once the pain has largely gone away, it’s important to begin to exercise the shoulder muscles. As you strengthen those muscles, the possibility of further subluxations will be reduced which is something you definitely want to avoid. Nevertheless, it may take several months before it has completely healed and the muscles have become strong enough to keep things in place, barring an extremely hard blow to the area. In short, the prognosis is usually good if you take the time and make the effort to treat the problem.
If subluxations reoccur to the point where they seem to become chronic, surgical intervention will quite likely be necessary as the tissues holding the bones of the joint in place will usually have become too loose and weakened to do so any longer. The medical term for this condition is chronic shoulder instability. A worst-case scenario is that of multidirectional instability where the shoulder is apt to feel permanently unstable and can dislocate in a number of different directions.
In more severe or chronic cases of shoulder subluxation, treatment generally involves repairing stretched or torn ligaments in the area around the joint.