Dislocations

Dislocations are injuries caused by a high-energy mechanism that results in the separation of two bones in a joint.

In a situation of shoulder instability, contact is lost between two of the joint cavities, the subacromial space and the glenohumeral joint. When this separation is not very long-lasting, we refer to it as a subluxation, but when it is long-lasting, it is a dislocation.

Depending on which parts of the joint are separated, we can talk about different types of dislocations:

• Glenohumeral instability (known as shoulder dislocation): the head of the humerus is projected forward and pops out of the anterior glenoid. This is the most common type of dislocation and is almost always caused by an impact to the arm that is transmitted to the shoulder, causing it to dislocate.
• Acromioclavicular dislocation: trauma to the shoulder causes a separation between the collarbone and the acromion.
• Clavicle dislocation: following trauma caused by a fall onto the shoulder, injury to the clavicle ligament occurs, resulting in dislocation and elevation of the clavicle.

Most dislocations occur in people who play contact sports or who perform continuous and intense joint movements. Depending on the degree of dislocation, the patient may only report pain and discomfort in their shoulder. In these cases, conservative treatment may be chosen, which, after intensive rehabilitation, can yield excellent results.

Once an objective dislocation has occurred, there is a greater chance that it will happen again (recurrent dislocation), in which case surgical treatment will be necessary. This surgery is usually performed arthroscopically, but in cases of recurrence after individualised analysis, it may be necessary to perform further arthroscopic surgery or open surgery.