B8. Scapula and clavicle fractures. Dislocation of the AC, SC and shoulder joints.

Page created on October 25, 2021. Last updated on October 27, 2021 at 12:37

Summary

  • Scapula fractures are rare. They’re mostly treated conservatively but surgical treatment is indicated for displaced or intraarticular fractures. A floating shoulder refers to fracture of the scapular neck and clavicle, which is also an indication for surgery
  • Clavicle fractures are common and often due to fall onto the shoulder. Fractures of the middle third of the clavicle accounts for most cases. Fracture fragments may cause pneumothorax or neurovascular injury. Treatment is conservative with a sling.
  • The shoulder is the most commonly dislocated joint, occuring mostly in young males. Most dislocations are anterior. Anterior dislocation occurs due to fall on extended, externally rotated arm, while posterior dislocation occurs during electrocution or seizure. Shoulder dislocations are often recurrent. A Bankart or Hill-Sachs lesion may be present on x-ray. Dislocations should be reduced under anaesthesia. Immobilisation and physiotherapy is important to prevent recurrence or frozen shoulder.
  • Acromioclavicular (AC) dislocation occurs due to rupture of the acromioclavicular and coracoclavicular ligaments due to direct trauma to shoulder. It is also known as a “separated shoulder”. They’re classified according to Rockwood or Tossy. The “piano key” sign may be present. Stress view on x-ray may be required. Treatment is conservative for type I – II and surgical for III – VI.
  • Sternoclavicular (SC) dislocation may be presternal or retrosternal. Retrosternal dislocation may injure mediastinal structures. They’re easy to reduce but difficult to retain. Conservative or surgical treatment may be used.

Scapula fracture

Definition and epidemiology

Scapula fractures are rare injuries. They usually involve the scapular neck, body, or glenoid cavity. There are often associated injuries.

A “floating shoulder” refers to ipsilateral fracture of the scapular neck and clavicle, causing the shoulder to “float” freely.

Etiology

These fractures may occur due to falls or high energy trauma.

Clinical features

Symptoms are typical fracture symptoms.

Diagnosis and evaluation

CT may be necessary preoperatively.

Treatment

Conservative therapy is used for fractures of the scapular body and of the scapular neck if there is no major dislocation. It involves a sling and early mobilisation.

Operative therapy is used for displaced neck fractures, when closed reduction is not possible, and if intraarticular. Floating shoulder is also an indication for operation.

Clavicle fracture

Definition and epidemiology

Clavicle fracture is relatively common.

Etiology

Clavicle fracture occurs due to fall onto the shoulder in 90% of cases. Direct blow and fall onto outstretched hand accounts for the remaining cases.

Classification

Clavicle fractures are classified as affecting the medial, middle, or lateral third of the bone. Middle fractures are the most common (80% of cases).

Clinical features

Palpation of the clavicle shows a specific painful point which corresponds to the site of the fracture. Pain worsens with movement of the shoulder. Dislocated fractures may be grossly visible.

These fractures may be associated with pneumothorax (due to bone fragments penetrating the pleural cavity), or more severe injuries on nerves and vessels.

Diagnosis and evaluation

X-ray is usually sufficient.

Treatment

Treatment is almost always conservative, with closed reduction and immobilisation with an arm sling. Operative treatment may be indicated for distal or open fractures, in which case ORIF with titanium nail or plate is used.

Dislocation of the AC, SC, and shoulder joints

Definition and epidemiology

Acromioclavicular (AC) joint dislocation occurs due to rupture of the acromioclavicular and coracoclavicular ligaments. It is also known as a “separated shoulder”.

Sternoclavicular (SC) joint dislocation is uncommon.

Shoulder dislocation is the most common joint dislocation, occurring mostly in younger males. It is often associated with other injuries, like fractures, tears of the rotator cuff, and injuries to the axillary artery or nerve. Shoulder dislocations are often recurrent as the joint capsule becomes lax after the first dislocation.

Etiology

AC dislocation occurs due to direct trauma to the shoulder, like rugby or ice hockey.

SC joint dislocation may be due to indirect injury or direct injury.

Anterior shoulder dislocation occurs due to fall on an extended, externally rotated arm, or due to direct trauma. Posterior dislocations occur due to overpulling of the subscapularis or latissimus dorsi muscles, due to electrocution or seizure.

Classification

AC dislocations are classified according to the Rockwood or Tossy classification.

SC dislocations may be presternal (caused by indirect injury) or retrosternal (caused by direct injury). Retrosternal dislocation may cause injury of mediastinal structures (vessels, nerves, and oesophagus).

Shoulder dislocations are classified according to the direction of the dislocation. Anterior dislocations are the most common (95%). Posterior and inferior dislocations are rare. Inferior dislocation is called luxatio erecta, due to the presentation.

Clinical features

AC dislocation presents with pain over the AC joint. In case of type III AC dislocation, the lateral cavity can be depressed manually, called the “piano key” sign.

SC dislocation presents with a deformity and a palpable bump on the clavicle.

Patients with shoulder dislocations present with severe shoulder pain, and usually use the unaffected arm to stabilise the affected arm to reduce movements. In case of anterior dislocation, the arm is in an adducted position. A gap below the acromion may be palpated, as well as the head of the humerus below the clavicle. In case of posterior dislocation, the arm is internally rotated and abducted. In case of luxatio erecta, the patient’s shoulder is locked in an overhead and abducted position.

Diagnosis and evaluation

Stress views (x-ray while weights are attached to the wrists) may be required to differentiate type I and II AC dislocations.

CT may be required to rule out mediastinal injury in SC dislocation.

Shoulder dislocations require x-ray before and after reduction. In case of posterior dislocation, the “lightbulb sign” and “vacant glenoid sign” may be seen. Associated injuries should be ruled out.

Bankart lesion refers to rupture of the anterior glenoid labrum and may be seen after reduction. Hill-Sachs lesion refers to a cortical depression on the posterior/lateral humeral head.

Treatment

AC dislocation is treated conservatively or operatively depending on the type:

  • Type I – conservative
  • Type II – conservative or operative
  • Type III – mostly operative
  • Type IV – VI – operative

Operative treatment involves ORIF with K-wire, tension band, or a plate.

SC dislocation is relatively easy to reduce but retaining this reduction may be difficult. Conservative therapy involves immobilisation. Operative therapy involves K-wire with resection of the proximal end of the clavicle.

Shoulder dislocations should be reduced under anaesthesia (usually general) or analgesia (like intraarticular lidocaine). There are multiple techniques for reduction (Hippocrates, Stimson, Snowbird). In case of failed closed reduction, Bankart lesion, or rotator cuff tear, surgery is indicated.

Reduction and operation should be followed by immobilisation and physiotherapy to prevent recurrence and frozen shoulder.


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B7. Foot fractures and dislocations. Achilles-tendon injuries

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B9. Proximal and middle shaft humeral fractures.

Parent page:
Traumatology

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