by Dr. Richard Cunningham
Here's a common patient question: "I recently fell skiing and dislocated my shoulder, and it was put back in place in the ER. What should I do now?"
Let's answer this. Shoulder dislocations are the most common joint dislocations. This is due to the fact that the shoulder socket is very shallow and thus inherently unstable.
The shallow shoulder socket allows for a great range of motion, but the disadvantage is that we are then dependent on our ligaments, tendons, and musculature for holding the ball in the socket.
By contrast, in a hip joint, the deep bony socket primarily contains the ball and therefore hip dislocations are uncommon. Shoulder dislocations most commonly occur in teenage, male patients but can occur in anyone.
How Do Shoulder Dislocations Occur?
Most shoulder dislocations occur when someone falls on an outstretched arm, and the arm is violently pushed backward. The top of the arm bone or humeral head then pops out the front or anteriorly.
Posterior and inferior dislocations are much less common. When a shoulder dislocates, the ligaments or labrum usually tears off the front of the socket. We call this a Bankart lesion. Patients are also left with a small impaction fracture along the back of the humeral head called a Hill-Sachs lesion.
What are the Symptoms of a Dislocated Shoulder?
An important nerve can be stretched with an anterior shoulder dislocation leaving the patient with temporary numbness and weakness of their deltoid muscle.
In middle-aged patients who dislocate their shoulder, there can be an associated rotator cuff tendon tear where the tendon is ripped off of the humerus when the humeral head dislocates. It is critical not to miss this associated injury as it can otherwise cause long term strength deficits and pain.
Reducing a Dislocated Shoulder
Most patients who dislocate their shoulder end up in an emergency room shortly thereafter. Here in the high country, we are very fortunate to have great ER docs who reduce a large number of shoulder dislocations and put them back into place quickly and traumatically.
There are multiple reduction techniques utilized, but these typically involve muscle relaxation, traction, and gentle manipulation.
Most techniques involve recreating the position of the arm when it dislocated thus unlocking the head from the edge of the socket and having the head slide back onto the socket. After reducing the shoulder, Xrays are used to confirm that the shoulder is reduced.
What If I Dislocate My Shoulder While in The Backcountry?
Patients sometimes ask me what to do if they are in the backcountry and they have another dislocation and there is no one to help them get the shoulder reduced.
I tell them that one reliable technique they can try is to do their best to relax their muscles and slowly try to reach their arm up as if they were trying to scratch the back of their head. After doing this, the shoulder should reduce.
What Happens After Shoulder Reduction?
After a successful shoulder reduction, patients are then placed in a sling for the first few weeks but are encouraged to come out of the sling and start some easy shoulder range of motion exercises. Hopefully, the patient has full range of shoulder motion by 4 weeks. Patients can resume all activities when they have full shoulder range of motion and strength but this can take up to 6-8 weeks.
For patients over the age of 40 who fail to improve their strength after the first few weeks, an MRI is obtained to rule out a rotator cuff tear. If there is a rotator cuff tear then surgery to repair this is usually recommended.
Younger patients (teenagers and early 20’s) do not usually tear their rotator cuff tendons when they dislocate, but they are at high risk of having future dislocations.
If a younger patient has further shoulder dislocations, they may come to an arthroscopic shoulder surgeon to repair the torn ligaments and labrum after their 2nd or 3rd dislocation of the shoulder.
This article first appeared in the Summit Daily news. https://www.summitdaily.com/sports/ask-a-sports-medicine-doc-treating-dislocated-shoulders/
Dr. Rick Cunningham
Dr. Rick Cunningham is a knee and shoulder sports medicine specialist with Vail-Summit Orthopaedics & Neurosurgery.
Learn more about Dr. Cunningham on his website: www.rcunninghamorthopedics.com