Shoulder pain is a common complaint in active and non-active people, alike. Musculoskeletal issues, such as overuse, strains, rotator cuff issues, poor exercise form and even sleeping awkwardly, can all cause pain in and around the shoulder blades. While arthritis, heart and lung conditions, shingles, gallstones and even liver disease can manifest as shoulder blade pain, these conditions are much less common causes of shoulder pain than musculoskeletal issues.
If you’re experiencing shoulder blade pain, pain between your shoulder blades or pain under your shoulder blades, it may be due to scapular dysfunction – officially known as scapular dyskinesis.
What is scapular dyskinesis?
Put simply, scapular dyskinesis is the abnormal function or mobility of the scapula (shoulder blade) within the shoulder joint.
The shoulder joint is a ball-and-socket joint made up of three bones: the humerus (upper arm bone) the scapula (shoulder blade) and the clavicle (collarbone). The top of the humerus forms the ball that sits within the glenoid (socket) of the scapula. While a complex system of muscles and tendons – including the rotator cuff – holds this ball-and-socket in place, the scapula acts as an anchor site for multiple muscles around the shoulder. The font of the shoulder blade (acromion) also attaches to the clavicle to create the acromioclavicular (AC) joint.
Scapular Dyskinesis and Common Shoulder Pain Causes
The scapula is designed to move in connection with your arm in order to keep the shoulder’s ball-and-socket joint in proper alignment. If an injury, stress or strain to the muscles or tendons in the shoulder causes weakness or imbalance, the position of the scapula can be affected. This, in turn, can cause limited mobility and shoulder blade pain.
Scapular dyskinesis: the surgeon’s perspective, an article published in the NIH’s US National Library of Medicine, concluded that there are high correlations between specific shoulder injuries and scapular dyskinesis:
- Labral injuries
- Shoulder impingement (also known as swimmer’s shoulder)
- Rotator cuff injuries
- AC joint injures
- Clavicle fractures
In addition to the acute injuries above, musculoskeletal issues – weak, tight or detached muscles that control the scapula – are the most common causes of shoulder blade pain.
These musculoskeletal issues are often attributed to overuse, repetitive motions (such as throwing or serving) and poor overhead movement mechanics. Scapular dyskinesis can also be caused by injuries to the nerves that supply these muscles.
Typical scapular dyskinesis symptoms include:
- Weakness in the arm on the affected side – including the arm feeling “dead” or “heavy”
- Pain and/or tenderness on and around the shoulder blade, particularly on the inner (medial) edge and at the top of the scapula
- Limited range of motion (unable to raise the arm above shoulder height)
- Unnatural “snapping” or “crunching” sound with shoulder rotation and movement
- Visible “winging” (protrusion) of the shoulder blade
- A drooped shoulder posture on the affected side
- Fatigue with overhead and/or repetitive movements
Scapular Dyskinesis Tests & Diagnosis
An orthopedic shoulder specialist will go over your symptoms, injury history, medical history and he or she will conduct a visual examination to look for tightness, weakness or signs of injury.
Manual Muscle Testing
This tests the strength – or lack thereof – in your shoulder and scapular muscles to determine if muscle weakness is a contributing factor to your shoulder pain and abnormal scapular positioning and/or motion.
Scapular Assistance Test (SAT)
The scapular assistance test helps determine if your muscles are strong enough to raise your arm on the affected side. Your shoulder doctor will apply pressure to your shoulder blade, helping it move up upward as you raise your arm. If your range of motion increases and your symptoms decrease, it is a good indication that the muscles are too weak for proper function.
Scapular Retraction Test
The scapular retraction test helps determine if scapular dyskinesis is present. Your doctor will push down on your extended arm to test its strength. Next, he or she will manually move the scapula into a retracted position and repeat the strength test. If your strength improved with the scapular manipulation, you most likely have scapular dyskinesis.
Finally, your orthopedic shoulder specialist will order X-rays, a CT scan or an MRI if he or she believes you may have an injury elsewhere in your shoulder or if you have any bony abnormalities on your scapula.
Scapular Dyskinesis Treatment & Surgery
Most cases of scapular dyskinesis can be treated with nonsurgical options, including nonsteroidal anti-inflammatory drugs (NSAIDs) to relieve pain and inflammation and physical therapy to strengthen the muscles that move and stabilize the scapula while stretching the muscles that are limiting full scapular mobility.
Scapular dyskinesis typically does not require shoulder surgery. If your condition was caused by a traumatic injury to the joint or surrounding muscles and tissues, your orthopedic shoulder surgeon may recommend surgical options followed by physical therapy.
If you have any questions about scapular dysfunctions, shoulder pain or your shoulder injury, please contact us and we’ll be happy to help.