All you need to know about a Popped (Dislocated) Shoulder
What is shoulder dislocation?
Shoulder dislocation is the most commonly observed joint dislocation because the shoulder joint is the most mobile joint of the body and provides a very high range of motion which facilitates overall movement through rotations and lifting functions. Your shoulder joint is a ball and socket joint. The movement of your arm is facilitated by this arrangement which has the head of your arm bone (humerus) perfectly fit into the joint socket (glenoid fossa) which is in turn a part of the larger shoulder blade (scapula). The arm is held in the socket by a fibrous ring of cartilage (labrum) which extends from the joint socket and holds onto the arm bone head like a sock. This arrangement is stabilised by a fibrous tissue in the joint capsule and also by ligaments and muscles surrounding the joint.
A dislocation occurs when the shoulder is thrown out of its position which means the head of your arm bone is moved out of the shoulder cavity. If the force at which the bone is thrown out is severe, it might damage the ligaments and muscles surrounding the shoulder joint causing a partial or complete tear.
Types of shoulder dislocation
The type of shoulder dislocation depends on the direction in which the dislocation has taken place and where the humeral head ends up after final dislocation.
- Anterior or Forward dislocation
This is the most common type of shoulder dislocation with an occurrence rate of more than 95%. Most anterior dislocations are sub-coracoid and only affect the muscles and ligaments in and around the shoulder joint. In very rare cases, the damage may also extend to the lower parts like the thoracic cavity. The major cause of shoulder dislocations is a hard fall or direct trauma to on an outstretched arm. During the dislocation, there is a good chance that the auxillary nerve might get damaged which in turn damages or paralyses the deltoid muscle. Damage to the deltoid muscle results in loss of the rounded look of the shoulder.
- Posterior or backward dislocation
Posterior dislocations are rarely observed in individuals and most of the times go unnoticed in elderly patients and trauma patients involved in accidents. Posterior dislocation is caused because of strength imbalance in the rotator cuff muscles with the arm rotating internally and the shoulder appearing flattened.
- Inferior or downward dislocation
This type of location mostly occurs when the arm bone head is forced against the acromion causing complications and injuries. The occurrence rate for this type is very low, as low as 1%.
- Causes of shoulder dislocation
Causes of dislocation are strenuous physical activity causing overuse of the shoulder joint, a hard fall or any other trauma to the shoulder, contact sports like football, hockey and baseball and any other activity that stretches your shoulder beyond the normal range.
With good medical attention you can recover from a dislocation injury within 12 to 16 weeks. In case of a popped shoulder, see your physio as soon as possible and begin the rehabilitation process!