What is a Shoulder Dislocation?
A shoulder dislocation is a common injury. It is commonly seen in athletes participating in contact sports, such as football and hockey. It is commonly caused by a fall and a hard landing on an outstretched arm. The ball at the top of the upper arm bone (head of the humerus) is forced completely out of the shoulder socket (glenoid) resulting in a shoulder (glenohumeral joint) dislocation. With a dislocated shoulder, the ligaments and labral tissue that hold the head of the humerus in the glenoid are completely torn. With shoulder subluxations, the humeral head only partially slides out of the glenoid. In shoulder subluxations, the ligaments holding the ball in the socket are stretched but do not completely tear.
In the event of an anterior shoulder dislocation, patients will experience immediate pain, there is typically fullness in the front of the shoulder as the humeral head is sitting out front, and there is very limited shoulder range of motion. Prompt orthopedic attention is required. Dr. Cunningham is a shoulder specialist at Vail Summit Orthopaedics and Neurosurgery. He is an expert at diagnosing and treating shoulder dislocations for patients in Vail, Summit County, Aspen, and Denver, CO.
What is the Most Common Type of Shoulder Dislocation?
The most common type of shoulder injury seen in emergency rooms are dislocated shoulder. An anterior shoulder dislocation is the most frequent type of dislocation–accounting for 95% of all shoulder dislocation cases. An anterior dislocation occurs when the humeral head is displaced out of the socket and comes toward the front of the body, or anteriorly, and slightly inferiorly.
Posterior shoulder dislocations account for 2% – 4% of all dislocated shoulders. In these, the humeral head is displaced out of the socket and goes toward the back of the body, or posteriorly. Posterior dislocations are commonly caused by seizures, electric shocks, or falling with the arm out across your body.
What Causes a Shoulder Dislocation?
Most dislocated shoulders occur as a result of a hard fall. Instinctively, we reach out to brace our fall and the head of the humerus comes out of the front of the socket. In some cases, the dislocation can also result in a fracture to the top of the humerus and/or to the tuberosities, which are the normal attachment sites of the the rotator cuff tendons adjacent to the humeral head.
The first priority is to get the ball back into the socket or reduce the glenohumeral joint. After this is accomplished, factors such as the age of the patient, one’s activity level, and whether one has sustained any prior dislocated shoulders, are all considered to determine the best treatment plan.
Symptoms of Shoulder Instability
Dislocated shoulders, whether they be anterior or posterior, initially cause:
- An extreme deformity of the shoulder with it being clearly out of place and patients knowing it is out of place
- Intense pain
- Near inability to move the shoulder
- Shoulder weakness
- Numbness and tingling down the arm
Accessing emergency medical care is recommended. In an emergency room, an xray will be obtained to assess the direction of the dislocation and to rule out any associated fractures that would prevent a reduction attempt in the ER. If there is no associated fracture and just a dislocation, the ER physician will utilize one of several reduction maneuvers to get the ball back in the socket. These techniques most commonly include the Stimson technique and FARES method. At times, relaxing medication is administered if a reduction is difficult to achieve. The upper extremity is then placed in a shoulder sling to immobilize the shoulder joint and protect it.
After the ball is put back into the socket and the joint properly aligned, patients commonly experience the following symptoms:
- Moderate pain made worse by sudden shoulder motions
- Apprehension when moving the shoulder away from the body
- Numbness and Tingling down the arm
- Popping and clicking sensations when moving the shoulder
Icing the shoulder after a dislocated shoulder is encouraged. Over the counter pain medications can be used if needed for pain. One can also slip out the sling to do some very limited shoulder range of motion exercises or to take a shower.
Does Shoulder Dislocation Require Surgery?
For young people (under the age of 30), there is a high likelihood that the shoulder will continue to dislocate in the future after one has sustained an initial dislocation. This is especially true in teenage males who participate in contact sports such as football. The reason there is a high recurrence rate is that with an initial dislocation, there is tearing of the labrum and the ligaments of the shoulder, and these do not heal in the proper position without surgery. Furthermore, certain sports, such as football, place such significant stresses on the shoulder that further dislocations are more likely. For this reason, most young patients come to arthroscopic surgery to have their labrum repaired back to the edge of the socket (glenoid) as well as tightening any stretched out ligaments. Following surgery, patients go home the same day in a sling, which is worn for 4 weeks. Patients come out of the sling immediately and start gentle physical therapy to slowly regain their shoulder range of motion and later their strength. Patients can be jogging or riding a bike by 6 weeks, but it could take 4 months to be cleared to play a contact sport like football.
For older patients (over the age of 50), there is less likely to be further dislocation events as most older patients do not participate in high risk sports such as football. However, there is more likely to be associated tears of the rotator cuff tendons following a shoulder dislocation as there is underlying wear and tear change in the tendons and they are more susceptible. Given this, Dr. Cunningham always recommends that an MRI be performed to check for rotator cuff tearing in anyone over the age of 50 or in patients who demonstrate rotator cuff weakness on a physical exam following a shoulder dislocation. If there is an associated rotator cuff tear, then arthroscopic surgery would be recommended to repair this tear as well as to fix the torn labrum in the shoulder.
Dr. Cunningham is a shoulder specialist at Vail Summit Orthopaedics and Neurosurgery. He is an expert at diagnosing and treating shoulder dislocations for patients in Vail, Summit County, Aspen, and Denver, CO. Contact Dr. Cunningham today.