Scapular Dyskinesis - Types, Causes, Symptoms, and Treatment

Introduction

The scapula is a large, triangular-shaped bone in the upper back. The scapula, also known as the shoulder blade, is important in coordinating and maintaining shoulder movements. Proper movement of the scapula is important for normal shoulder movements. The glenohumeral joint is a ball and socket joint that comprises the glenoid fossa of the scapula and the rounded side of the humerus bone( upper arm); the rotator cuff muscles support this joint. The glenohumeral joint, along with the rotator cuff, helps in the three-dimensional movements of the shoulder. Any abnormality in the anatomy or the function of the scapula affects the upper limb movements.

What Is Scapular Dyskinesis?

Scapular dyskinesis is defined as any changes in the position or movements of the scapula. Scapular dyskinesis increases the chances of shoulder injuries by altering the strength and tension of the surrounding muscles.

What Are the Types of Scapular Dyskinesis?

Scapular dyskinesis is classified clinically into three types.

• Type I -Infero-medial scapular border prominence:

In type I, there is a posterior displacement of the inferior medial angle of the scapula. It is common in the early stages of shoulder disorders.

• Type II - Medial border prominence:

In this type, the entire medial border of the scapula is posteriorly displaced. The fatigue of surrounding muscles causes it.

• Type III - Superomedial border prominence:

The scapular elevation, or superior border, is prominent in this type.

What Are the Causes of Scapular Dyskinesis?

The common contributing factors to scapular dyskinesis include:

• Injury to the joints.

• Loss of flexibility in the entire shoulder joint.

• Damage to the nerves that supply the muscles.

• Injury or fatigue to the muscles supporting the shoulder joint.

• Weak bones

• Bone fractures.

• Weak core, hips, and legs.

Neck-Related Causes:

Scapular dyskinesis, which may be caused by neck-related problems, is mainly related to mechanical neck pain syndromes and cervical nerve root-related syndromes.

• Mechanical neck pain syndromes are pathologies affecting the muscles and joints of the neck. It is most commonly caused by poor posture.

• Cervical nerve-related pathologies occur when the cervical nerves improperly activate one or more nerves around the scapula. Nerve pathologies may lead to the scapula's disorganized movements, leading to scapular dyskinesis.

Shoulder-Related Causes:

Shoulder-related pathologies are the most common cause of scapular dyskinesis. Most shoulder pathologies are associated with scapular dyskinesis. Some of the common ones are listed below.

• Shoulder impingement.

• Rotator cuff injuries.

• Acromioclavicular instability.

• Clavicle fracture.

• Glenoid labrum injuries.

• Nerve-related causes.

Posture-Related Causes:

Exaggerated thoracic kyphosis and cervical lordosis may alter the position of the scapula. In addition, athletes are more prone to posture-related scapular dyskinesis.

What Are the Symptoms of Scapular Dyskinesis?

• Pain and tenderness around the scapula, mainly when the hands are raised above the head or when lifting heavy objects.

• Feeling a snap or pop while moving the shoulder joint.

• The arm on the affected side feels weaker.

• Shoulders appear asymmetrical.

• Noticeable protrusion of the scapula (shoulder blades sticking out like wings).

• Range of motion is limited on the affected side; lifting the arms above the shoulders becomes difficult.

What Are the Conditions That Increase the Risk and Severity of Scapular Dyskinesis?

• Poor physical condition, including strength and flexibility.

• Sports that involve overhead activity.

• Using poor techniques to throw or lift objects.

• Chronic inflammation.

• Stiffness of the shoulder.

• Previous or repeated shoulder injuries.

• Loose joints.

• Poor posture.

How Is Scapular Dyskinesis Clinically Diagnosed?

Clinical Assessment:

Usually, scapular dyskinesis is diagnosed by the physician during a clinical examination. Clinical assessment is done in the following three steps.

• Direct Observation of the Scapula - The resting position of the scapula is observed. The scapula is observed during action by making the patient do simple movements involving the shoulder joint.
• Manually Assisted Movements - Two tests are done: the scapular assistance test and the scapular reposition test.
• Assessment of Surrounding Structures - The structures surrounding the scapula, like the acromioclavicular joint, the thoracic spine, the rotator cuff muscles, and other structures, are assessed thoroughly by the physician to rule out or check for the other causes of the symptoms.

Other Diagnostic Tests:

Clinical assessment is enough to diagnose scapula dyskinesis in most cases. Additional tests are done to identify the cause of scapular dyskinesis. CT scans, especially four-dimensional CT scans, may be done to assess the scapular position and the soft tissue. MRI scans are done to locate any inflammation or lesions causing scapular dyskinesis.

How Is Scapular Dyskinesis Treated?

Conservative Treatment Measures:

• Physiotherapy is the main treatment option for scapular dyskinesis. It aims to reduce symptoms and rehabilitate the shoulder.

• Stretching of the affected structure is done. Some stretches are unilateral corner stretches, sleep stretches, and cross-body stretches.

• Rehabilitation of the muscles is done in three stages.

  1. Active Conscious Control - conscious training of the muscles is done using physiotherapy exercises. The patient is also taught to maintain a neutral spine position.
  2. Strength and Control for Daily Activities - This includes open-chain and closed-chain exercises. Open chain activities include low row, lawn mower, inferior glide, and robbery exercises.
  3. Control in Athletic Performance - For athletes, depending on the sport, muscle-strengthening exercises are taught with specific principles depending on their requirements.

• NSAIDs are given to help with the pain symptoms.

• Heat and cold therapy are advised.

Surgical Treatment Measures:

• Surgical treatment is required in soft tissue-related pathologies like labral injury, rotator cuff injury, or internal impingement.

• Surgery is also required in hard tissue-related conditions like fractures or shoulder separation.

• Once the underlying problem is corrected using surgery, physiotherapy is done to address the scapular dyskinesis.

What Are the Complications of Scapular Dyskinesis?

• Healing time may be prolonged if not treated properly.

• Loss of motion in the shoulder or shoulder stiffness.

• Recurrence of symptoms may happen if activities are resumed too soon or poor techniques are used.

• Chronic inflammation may lead to constant pain.

• Rotator cuff tendon tear.

When Should the Doctor Be Consulted for Scapular Dyskinesis?

The patient should consult the doctor immediately if:

• Pain and other symptoms worsen even after the treatment.

• Numbness in the arms.

• The appearance of new and unexplained symptoms.

• Fingernails become blue or gray.

Conclusion:

The management of scapular dyskinesis hinges upon the recognition of its treatability and the effectiveness of physiotherapy interventions. As evidenced by growing research, physiotherapy plays a major role in improving scapular dyskinesis, often yielding significant advancements in patient outcomes. The key to successful treatment lies in the accurate clinical assessment of scapular function, enabling exercise prescriptions that address underlying dysfunctions.