Snapping scapula syndrome

Overview

Snapping scapula syndrome is a musculoskeletal condition characterized by an audible or palpable snapping, grinding, or popping sensation around the shoulder blade (scapula) during arm or shoulder movements. This condition can be painful and interfere with shoulder mobility and function, especially in individuals who engage in repetitive overhead motions, such as swimmers, weightlifters, or throwing athletes.

The syndrome arises due to abnormal contact or friction between the scapula and the underlying rib cage or surrounding soft tissues. It may be associated with anatomical abnormalities, inflammation, or muscular imbalances that alter the smooth gliding motion of the scapula over the thoracic wall.

Causes

Snapping scapula syndrome can result from a variety of structural or functional abnormalities that disturb the normal biomechanics of scapulothoracic motion:

• Bony abnormalities: Prominent scapular edges, osteochondromas, or healed rib fractures can create irregular surfaces that cause snapping during movement.

• Inflammation: Bursitis (inflammation of the scapulothoracic bursa) is a common cause. The bursa normally facilitates smooth motion, and its inflammation can lead to painful friction.

• Muscle imbalance or weakness: Weakness in the periscapular muscles (such as the serratus anterior or lower trapezius) can result in scapular winging or abnormal positioning, increasing the likelihood of friction.

• Postural dysfunction: Poor posture, such as forward shoulder positioning or kyphosis, may contribute to scapular dyskinesis and snapping.

• Repetitive overuse: Repeated overhead or forceful arm movements can lead to wear and tear of the soft tissues and contribute to chronic irritation.

Symptoms

The main features of snapping scapula syndrome include:

• Snapping, popping, or grinding sensation at the upper back or shoulder blade during movement

• Audible crepitus (grating sound) when raising or rotating the arm

• Pain or discomfort along the scapula or upper thoracic region

• Tenderness over the scapulothoracic area, especially with pressure

• Limited range of motion or stiffness in the shoulder

• Fatigue or weakness in the shoulder and upper back muscles

Symptoms may worsen with physical activity, particularly during overhead movements or exercises involving the shoulder girdle.

Diagnosis

Diagnosis of snapping scapula syndrome involves a comprehensive physical examination and imaging studies to determine the underlying cause:

• Clinical examination: Palpation of the scapulothoracic area during active and passive arm movements to detect snapping or crepitus. Assessment of posture and scapular movement patterns.

• X-rays: Can reveal bony abnormalities such as osteochondromas or healed fractures.

• MRI: Useful for detecting soft tissue issues such as bursitis, muscle atrophy, or inflammation.

• CT scan: Offers detailed visualization of bony structures and helps plan surgical interventions if needed.

• Dynamic ultrasound: May be used to visualize scapulothoracic movement in real time and detect abnormal friction.

Treatment

Treatment for snapping scapula syndrome depends on the severity and underlying cause. Non-surgical interventions are typically tried first:

Conservative Treatment

• Rest and activity modification: Avoidance of aggravating activities that involve overhead or repetitive shoulder motion.

• Physical therapy: Focused on strengthening the periscapular muscles, correcting postural abnormalities, and improving scapular mechanics.

• NSAIDs: Nonsteroidal anti-inflammatory drugs help reduce inflammation and relieve pain.

• Corticosteroid injections: Targeted injections into the scapulothoracic bursa to reduce inflammation and provide temporary relief in cases of bursitis.

• Ice and heat therapy: May help manage pain and inflammation in the affected area.

Surgical Treatment

• Surgery may be considered for patients who do not respond to conservative treatment over a period of 3 to 6 months. Surgical options include:

  • Scapulothoracic bursectomy: Removal of the inflamed bursa.

  • Partial scapular resection: Removal of bony protrusions causing mechanical friction.

  • Arthroscopic techniques: Minimally invasive surgery may be used to address soft tissue or bony abnormalities.

Prognosis

The prognosis for snapping scapula syndrome is generally favorable, especially when diagnosed early and managed appropriately. Most individuals respond well to non-surgical treatment, with significant improvement in symptoms and function.

For patients requiring surgery, outcomes are typically good, particularly when performed by experienced orthopedic surgeons. Postoperative rehabilitation is essential to restore normal scapular motion and prevent recurrence.

With proper physical therapy, ergonomic adjustments, and ongoing muscle conditioning, many individuals can return to full activity, including sports and overhead work, without persistent symptoms.