B8. Scapula and clavicle fractures. Dislocation of the AC, SC and shoulder joints.
Scapula fracture
Scapula fractures are rare injuries. They usually involve the scapular neck, body, or glenoid cavity. There are often associated injuries. They’re mostly treated conservatively but surgical treatment is indicated for displaced or intraarticular fractures.
A “floating shoulder” refers to ipsilateral fracture of the scapular neck and clavicle, causing the shoulder to “float” freely. Floating shoulder is an indication of surgery.
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
Clavicle fracture is relatively common. They primarily occur 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.
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.
AC dislocation
Acromioclavicular (AC) joint dislocation occurs due to rupture of the acromioclavicular and coracoclavicular ligaments. It is also known as a “separated shoulder”. It occurs due to direct trauma to the shoulder, like rugby or ice hockey. 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.
Classification
AC dislocations are classified according to the Rockwood or Tossy classification.
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.
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.
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
Sternoclavicular (SC) joint dislocation is an uncommon injury. It may be due to due to indirect trauma or direct trauma.
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). They’re easy to reduce but difficult to retain. Conservative or surgical treatment may be used.
Clinical features
SC dislocation presents with a deformity and a palpable bump on the clavicle.
Diagnosis and evaluation
CT may be required to rule out mediastinal injury in SC dislocation.
Treatment
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 dislocation
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. 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.
Shoulder dislocations are often recurrent as the joint capsule becomes lax after the first dislocation. This is called recurrent shoulder dislocation.
Etiology
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
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.
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.
Clinical features
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
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.
Treatment
Shoulder dislocations should be reduced under anaesthesia (usually general) or local 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.