Sternoclavicular (SC) Joint Dislocation: Understanding, Diagnosis, and Treatment

How do you fix a dislocated sternoclavicular joint?

Fixing a dislocated sternoclavicular (SC) joint is a medical procedure that requires immediate professional attention from a physician or orthopedic specialist, often involving manual reduction techniques or, in complex cases, surgical intervention, followed by a structured rehabilitation program.

Understanding the Sternoclavicular (SC) Joint

The sternoclavicular (SC) joint is a critical articulation connecting the upper limb to the axial skeleton. It is formed by the medial end of the clavicle (collarbone) and the manubrium of the sternum (breastbone). Despite its relatively small size, the SC joint is surprisingly robust, reinforced by strong ligaments: the anterior and posterior sternoclavicular ligaments, the interclavicular ligament, and the costoclavicular ligament. This joint allows for significant mobility, primarily elevation, depression, protraction, retraction, and circumduction of the clavicle, which are essential for full range of motion of the shoulder complex. Its stability is paramount for shoulder function and protection of vital structures in the superior mediastinum.

What is a Sternoclavicular Joint Dislocation?

A sternoclavicular joint dislocation occurs when the clavicle separates from the sternum. While relatively rare, accounting for less than 5% of all dislocations, it is a significant injury. These dislocations are typically the result of high-energy trauma, such as direct impact to the anterior chest or a fall onto the shoulder. They are classified based on the direction of displacement of the medial clavicle relative to the sternum:

• Anterior Dislocation: The medial end of the clavicle displaces forward (anteriorly) over the sternum. This is the more common type, often less severe in terms of immediate complications.
• Posterior Dislocation: The medial end of the clavicle displaces backward (posteriorly) behind the sternum. This is a far more serious injury due to the proximity of vital structures in the superior mediastinum, including the trachea, esophagus, subclavian artery and vein, and major nerves. Posterior dislocations are considered medical emergencies.

Recognizing the Signs and Symptoms

Prompt recognition of an SC joint dislocation is crucial for effective treatment. Common signs and symptoms include:

• Severe Pain: Localized pain at the SC joint, often exacerbated by arm movement, deep breathing, or lying flat.
• Visible Deformity: A palpable bump or depression at the joint, indicating displacement of the clavicle. In anterior dislocations, a prominent bulge may be seen; in posterior dislocations, a depression may be present, or the affected shoulder may appear shortened and protracted.
• Swelling and Bruising: Inflammation and ecchymosis around the joint are common.
• Limited Range of Motion: Difficulty and pain with movements of the arm, especially elevation, protraction, and retraction of the shoulder.
• Referred Pain: Pain may radiate into the neck or shoulder.
• Respiratory or Vascular Symptoms (Posterior Dislocation): In posterior dislocations, pressure on adjacent structures can cause:
  • Dyspnea (shortness of breath) or difficulty swallowing (dysphagia) if the trachea or esophagus is compressed.
  • Hoarseness if the recurrent laryngeal nerve is affected.
  • Paresthesia (numbness/tingling) or weakness in the arm due to nerve compression.
  • Diminished pulses or pallor in the affected arm due to subclavian vessel compression.

Diagnosis: The Critical First Step

Accurate diagnosis is essential to determine the type and severity of the dislocation and to rule out associated injuries.

• Clinical Examination: A thorough physical examination by a physician will involve visual inspection, palpation of the joint, assessment of range of motion, and neurological and vascular checks, particularly for posterior dislocations.
• Imaging Studies:
  • Plain Radiographs (X-rays): Standard X-rays can be challenging to interpret for SC joint injuries due to overlapping bony structures. Specific views, such as the serendipity view (cephalic tilt view), may improve visualization.
  • Computed Tomography (CT) Scan: This is the gold standard for diagnosing SC joint dislocations. A CT scan provides detailed cross-sectional images, clearly showing the direction and degree of clavicular displacement and identifying any associated fractures or mediastinal compromise.
  • Magnetic Resonance Imaging (MRI): While less frequently used for initial diagnosis of acute dislocations, an MRI can be valuable for assessing soft tissue damage, including ligamentous tears and articular cartilage injuries, particularly in chronic cases or when surgical planning is required.

Medical Management: Fixing an SC Joint Dislocation

The "fix" for an SC joint dislocation is a medical procedure performed by a qualified healthcare professional. Self-reduction attempts are strongly discouraged and can lead to further injury, especially with posterior dislocations.

Immediate Medical Attention

Any suspected SC joint dislocation, especially a posterior one, warrants immediate emergency medical evaluation.

Reduction Techniques

The primary goal of treatment is to reduce (realign) the dislocated joint.

• Closed Reduction (Non-Surgical):

  • Indication: Primarily used for anterior SC joint dislocations. It may be attempted for acute posterior dislocations if there are no signs of mediastinal compromise.
  • Procedure: Performed under conscious sedation or general anesthesia to relax muscles and minimize pain.
    • For anterior dislocations, the patient is typically supine with a bolster placed between the scapulae. The physician applies traction to the arm, often with an assistant stabilizing the shoulder, while directly manipulating the medial clavicle back into place.
    • For posterior dislocations, the technique is similar but aims to pull the clavicle anteriorly. A common method involves placing the patient supine with a bolster, adducting and extending the arm, and applying traction while an assistant may grasp the clavicle with fingers or even use a sterile towel clip to pull it anteriorly.
  • Success Rate: Generally high for acute anterior dislocations. Acute posterior dislocations also have a good success rate with closed reduction, but require careful monitoring.

• Open Reduction (Surgical):

  • Indication: Primarily indicated for posterior SC joint dislocations that cannot be reduced closed, are unstable after closed reduction, or present with signs of neurovascular or tracheal compression. It may also be considered for chronic anterior dislocations causing significant pain or dysfunction, or for acute anterior dislocations that are irreducible.
  • Procedure: Involves an incision to directly visualize the joint and surrounding structures. The clavicle is manually guided back into its anatomical position. Often, internal fixation (e.g., sutures, plates, or pins) is used to stabilize the joint while ligaments heal. Due to the high risk of complications with hardware migration into the mediastinum, the use of pins or wires is generally avoided or used with extreme caution and removed early. Ligamentous reconstruction using autograft or allograft tissue may be performed to enhance stability.
  • Considerations: Open reduction for posterior dislocations is a complex procedure due to the proximity of vital structures and is typically performed by experienced orthopedic or thoracic surgeons.

Post-Reduction Management

Following successful reduction, regardless of the method, the joint requires immobilization to allow for soft tissue healing.

• Immobilization: A sling or figure-of-eight brace is typically worn for 3-6 weeks to limit movement and protect the healing joint. The duration depends on the dislocation type, stability post-reduction, and physician preference.
• Pain Management: Analgesics (e.g., NSAIDs, acetaminophen) are prescribed to manage pain and discomfort.
• Follow-up Imaging: Post-reduction X-rays or CT scans are often performed to confirm successful reduction and monitor for any re-dislocation.

Rehabilitation: Restoring Function and Strength

Rehabilitation is a critical phase following SC joint dislocation treatment, focusing on restoring range of motion, strength, and functional capacity. This process is guided by a physical therapist and progresses through several phases.

• Phase 1: Immobilization and Pain Management (0-3/6 weeks)
  • Goal: Protect the healing joint, reduce pain and swelling.
  • Interventions: Strict adherence to immobilization protocol. Gentle, passive range of motion exercises for adjacent joints (elbow, wrist, hand) to prevent stiffness. Ice and pain medication as needed. No active shoulder or SC joint movements.
• Phase 2: Early Range of Motion and Gentle Strengthening (3/6-12 weeks)
  • Goal: Gradually restore pain-free range of motion, initiate gentle strengthening.
  • Interventions: Gradual weaning from immobilization. Passive and active-assisted range of motion exercises for the shoulder and SC joint, progressing to active range of motion. Isometric exercises for shoulder musculature (e.g., deltoids, rotator cuff) without stressing the SC joint. Scapular stabilization exercises. Emphasis on good posture.
• Phase 3: Progressive Strengthening and Functional Return (12+ weeks)
  • Goal: Restore full strength, endurance, and prepare for return to activity.
  • Interventions: Progressive resistance exercises for all shoulder and upper body musculature. Focus on compound movements. Advanced scapular stabilization drills. Proprioceptive training. Sport-specific or activity-specific drills, gradually increasing intensity and complexity. Close monitoring for recurrence or instability.

Potential Complications

While most SC joint dislocations heal well with appropriate treatment, potential complications include:

• Recurrence: Re-dislocation can occur, particularly with inadequate healing or premature return to activity.
• Chronic Pain and Instability: Persistent pain, clicking, or a feeling of instability at the joint.
• Post-Traumatic Arthritis: Long-term degeneration of the joint cartilage, leading to pain and stiffness.
• Neurovascular Compromise (Posterior Dislocation): Although usually resolved with successful reduction, persistent compression of the brachial plexus, subclavian vessels, trachea, or esophagus can lead to serious, long-term issues.
• Hardware Complications: If surgical fixation is used, issues like infection, loosening, or migration of hardware (especially dangerous near the mediastinum) can occur.

Prognosis and Return to Activity

The prognosis for SC joint dislocations is generally good with proper medical management and rehabilitation.

• Anterior Dislocations: Typically have a favorable outcome, with most individuals returning to full activity within 3-4 months.
• Posterior Dislocations: While more serious initially, successful reduction usually leads to good outcomes. However, the recovery period may be longer, potentially 4-6 months or more, especially if surgery was required.

Return to sport or demanding physical activities is a gradual process, guided by clinical assessment, resolution of pain, restoration of full strength and range of motion, and confidence in the joint's stability. Contact sports or activities with a high risk of re-injury require careful consideration and often a longer period of protective rest.

Prevention Strategies

While many SC joint dislocations result from unavoidable high-energy trauma, general strategies to reduce injury risk include:

• Proper Technique and Equipment: In sports, ensure correct form and use appropriate protective gear.
• Strength and Conditioning: Maintain overall shoulder and core strength to enhance stability of the entire shoulder girdle.
• Fall Prevention: Be mindful of surroundings to prevent falls, especially in older adults or individuals with balance issues.

In conclusion, "fixing" an SC joint dislocation is a multifaceted process that begins with immediate medical evaluation, followed by either closed or open reduction, and culminates in a comprehensive rehabilitation program. Understanding the anatomy, injury mechanisms, and treatment pathways is crucial for effective recovery and restoration of function.