Abnormalities of the Blade

The scapula, or shoulder blade, is a large triangular-shaped bone that lies in the upper back. The bone is surrounded and supported by a complex system of muscles that work together to help you move your arm. If an injury or condition causes these muscles to become weak or imbalanced, it can alter the position of the scapula at rest or in motion.

 

An alteration (change) in scapular positioning or motion:

• Can make it difficult to move your arm, especially when performing overhead activities
• May cause your shoulder to feel weak
• Can lead to injury if the normal ball-and-socket alignment of your shoulder joint is not maintained

Treatment for scapular disorders usually involves physiotherapy designed to strengthen the muscles in the shoulder and restore the proper position and motion of the scapula.

Abnormal scapula movements is a common physical sign, but because it is often asymptomatic it receives little attention. However, symptoms of pain, weakness, or cosmetic deformity may demand attention. True Winging of the scapula is rare. 

Winging may be caused by injury or dysfunction of the muscles themselves or the nerves that supply the muscles.

Your shoulder joint is a ball-and-socket joint. The head of the humerus (upper arm bone) is the ball and the scapula (shoulder blade) forms the socket.

The scapula and arm are connected to the body by multiple muscles and ligament attachments. The front of the scapula (acromion) is also connected to the clavicle (collarbone) through the acromioclavicular joint.

As you move your arm around your body, your scapula must also move to maintain the ball and socket in normal alignment.

This photo shows a patient with a “winged” scapula (arrow). Note the prominence of the medial (inner) border of the bone.

Disorders of the scapula resulting in a deviation, or alteration, in the:

• The normal resting position of the scapula, or
• Normal motion of the scapula as the arm moves

The medical term for these alterations is scapular dyskinesis (“dys”= alteration of, “kinesis” = movement).

In most cases, alterations of the scapula can be seen by looking at the patient from behind. The medial (inner) border of the affected shoulder blade will appear more prominent than the one on the opposite side. This prominence will often be exaggerated as the patient moves their arm away from the body. This is commonly called a “winged” scapula.

Cause

Causes of scapular dyskinesis include:

• Weakness, imbalance, tightness, or (rarely) detachment of the muscles that control the scapula
• Injuries to the nerves that supply the muscles
• Injuries to the bones that support the scapula or injuries within the shoulder joint

Symptoms

The most common symptoms of scapular dyskinesis include:

• Pain and/or tenderness around the scapula, especially on the top and medial (inner) border
• Weakness in the affected arm — your arm may feel tired or “dead” when you try to use it vigorously
• Fatigue with repetitive activities, especially overhead movements
• Limited range of motion — you may be unable to raise your arm above shoulder height
• A crunching or snapping sound with shoulder movement
• Noticeable protrusion or “winging” of the scapula
• A drooped or forward-tilted posture on the affected side

Home Remedies

In some cases, the symptoms of scapular dyskinesis may improve with simple home treatment that includes:

Restoring good posture. As you perform your everyday activities, try to stand and sit properly. To do this, pull your shoulder blades back together, and bend your elbows down and back as if you are trying to put them in your back pockets.

Balancing your exercise routine. If you are in a regular exercise program, make sure your upper body strength sessions are balanced. For every set of “presses” that you perform, you should do one set of “flys” and two sets of “rows.” Your program should also include stretching exercises for your front shoulder muscles and for shoulder joint rotation.

Heat therapy. Soaking in a hot bath or using a heating pad may help alleviate tight shoulder muscles.

If your symptoms persist, it is important to contact your doctor. They can help determine the exact cause of your dyskinesis and provide treatment options.

Doctor Examination

Physical Examination

Your doctor will talk with you about your medical history and general health and ask about your symptoms. They will examine your entire shoulder and scapula, looking for injury, weakness, or tightness. In most cases, the physical exam will include the following:

Visual observation. Prof Imam or a member of the team will look at your affected scapula from behind, comparing it to the non-involved side. To see if scapular dyskinesis is present, your doctor may ask you to move your arms up and down 3 to 5 times, sometimes with light weights in your hands. This will usually reveal any weakness in the muscles and display abnormal motion patterns.

Manual muscle testing. Your doctor will perform strength testing of your shoulder and scapular muscles to determine if muscle weakness is contributing to the abnormal scapular motion.

Corrective manoeuvres. Specific tests involve corrective manoeuvres that will help your doctor learn more about your condition. These tests include:

• Scapular assistance test (SAT). In this test, the doctor will apply gentle pressure to your scapula to assist it upward as you elevate your arm. If your symptoms are relieved and the arc of motion is increased, it is an indication that your muscles are not strong enough to raise your arm.

In the scapular assistance test, Prof Imam manually assists the scapula upward as the patient elevates their arm.

• Scapular retraction test (SRT). In this test, the doctor will test your arm strength by pushing down on your extended arm. They will then manually place the scapula in a retracted position and test your strength again. In patients with scapular dyskinesis, muscle strength will improve when the shoulder blade is retracted.

In the scapular retraction test, Prof Imam manually retracts the scapula while pushing down on the patient’s extended arm.

Imaging Tests

Imaging tests are not always necessary to diagnose scapular dyskinesis. Your doctor may, however, order an imaging study, such as an X-ray, computed tomography (CT) scan, or magnetic resonance imaging (MRI) scan, if they suspect a bony abnormality of the scapula (such as an osteochondroma) or an injury to another part of the shoulder.

Treatment

Physiotherapy exercises will focus on strengthening and stretching the muscles around the shoulder.

Nonsurgical Treatment

In almost all cases, the symptoms of scapular dyskinesis will improve with nonsurgical treatment.

Nonsurgical treatment may include:

Nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen and naproxen, can help relieve pain and swelling.

Physiotherapy. Prof Imam or a member of the physiotherapy team will provide an exercise program that targets the specific causes of your dyskinesis.

Physiotherapy usually focuses on:

• Strengthening the muscles that stabilize and move the scapula
• Stretching the tight muscles that are limiting scapular motion

Surgical Treatment

Most patients who have general dyskinesis due to muscle weakness or tightness do not need surgery.

However, if your dyskinesis is being caused by an injury to your shoulder joint, your doctor may perform a procedure to repair or reconstruct the injured tissues. This will be followed by rehabilitation to restore the scapula’s normal motion.

Long-Term Outcomes

Once the causes of your dyskinesis have been addressed and normal scapular position and motion are restored, your doctor may recommend a maintenance conditioning program of flexibility and strengthening. This is especially important if your job or recreational activities involve vigorous or repetitive shoulder and arm movements. These exercises should be done 3 times a week or as recommended by your doctor.

SCAPULAR WINGING 

Scapula Winging

The shoulder blade is the largest bone of the shoulder complex and has the greatest number of muscles attached to it. These muscles both stabilise the arm to the body and move the arm around in space. All these muscles act at the same time sometimes and oppose each other at other times, but work together like a well-trained team to allow the arm to move in space. If any of these muscles are not working in the right way at the right time this leads to a break in the rhythmic motion of the scapula. This is known as a scapula ‘ dysrhythmia ‘. This leads to the apparent ‘winging’ of the scapula.

Causes:

1. Loss of serratus anterior muscle function

When one talks about winging of the scapula, true winging is due to serratus anterior muscle dysfunction. This is an uncommon condition and may arise from traumatic injury to the nerve supplying the serratus anterior muscle, the long thoracic nerve; or due to damage to the nerve from pressure lesions or a neuritis (inflammation of the nerve). The long thoracic nerve follows a long an tortuous course from the neck to the serratus anterior muscle. It is prone to injury as it is much more vulnerable than many of the other nerves of the brachial plexus.
The test for identifying a long thoracic nerve injury is the ‘serratus wall test’. The patient is asked to face a wall, standing about two feet from the wall and then push against the wall with flat palms at waist level.

Nerve conduction studies and EMG tests of the long thoracic nerve, serratus anterior muscle and other muscles of the shoulder blade are beneficial to diagnose and quantify the degree of nerve and muscle damage. The tests are also useful to assess and follow the recovery of the nerve.
The treatment will depend on the cause and severity of the injury. Exploration and decompression of the nerve can be performed, where it gets trapped or damaged at the scalene muscles in the neck. For more advanced cases, the Pectoralis muscle can be performed.

2. Loss of trapezius muscle function

The trapezius muscle is a large muscle above your scapula which lifts and rotates your scapula. It is the muscle you use to shrug your shoulders.
Isolated loss of trapezius function is extremely rare and may occur after radical neck surgery (for tumours), where the nerve supplying the trapezius may be damaged (the spinal accessory nerve).
Many people can manage with loss of trapezius function, but some have weakness and difficulty with manual and overhead activities. If the diagnosis is made early, then surgical reconstruction of within 20 months of the injury the nerve or nerve release (neurolysis) should be considered 

3. Weakness of all the scapula stabilisers

Muscular dystrophies, most commonly facioscapulohumeral dystrophy  (FSHD), are the main cause of the weakness of all the scapula stabilising muscles.

4. Loss of scapular suspensory mechanism

The coracoclavicular ligaments suspend the scapula from the clavicle and the acromioclavicular joint is the only joint linking the scapula to the rest of the body. Therefore Acromioclavicular joint dislocation or fracture of the outer third of the clavicle, with rupture of the coracoclavicular ligaments, leads to an abnormal scapula rhythm and apparent scapula winging with overhead manoeuvers. This is usually not painful and usually only affects overhead workers and athletes.

Another rare cause is the ‘scapulothoracic dissociation’, described by Rockwood & Matsen in 1990. The scapula is wrenched from the body in violent trauma leading to fracture of the clavicle and soft tissues around the clavicle.

5. Winging of the scapula secondary to instability

This is one of the commonest causes of scapula dysrhythmias (and winging). Recurrent dislocations of the shoulder lead to dysfunction of the muscles that move and support the shoulder complex and scapula. The more frequent the dislocations and the less trauma involved in causing the dislocations, the worse the scapula dysrhythmia (winging). An essential part of treating shoulder instability (recurrent dislocations) is treating scapula dysrhythmia. This is done by an experienced physiotherapist in association with a shoulder surgeon.   

6. Winging secondary to pain

This is another common cause of secondary winging and dysrhythmia of the scapula. Any painful condition of the shoulder will lead to abnormal movements of the entire shoulder complex. Reduced movement at the glenohumeral joint will lead to more compensatory movement at the scapula.        

7. Brachial Plexus injury or disease

Most of the nerves supplying the stabilising muscles of the scapula arise from the Brachial Plexus. The Brachial Plexus is a bundle of nerves running from the neck to the arm. It carries the nerve supply for the muscles of the arm and shoulder. Sometimes a major accident can affect the muscles of the shoulder more than the arm and lead to winging. When there is no trauma, a condition known as Parsonage-Turner syndrome (Brachial Neuritis) can lead to weakness of the scapula muscles.