Scapulothoracic Dissociation

• This injury is a traumatic disruption of the scapula from the posterior chest wall.

• This rare, life-threatening injury is essentially a subcutaneous fore-quarter amputation.

• The mechanism is a violent traction and rotation force, usually as a result of a motor vehicle or motorcycle accident.

• Neurovascular injury is common:

  • Complete brachial plexopathy: 80%

  • Partial plexopathy: 15%

  • Subclavian or axillary artery: 88%

• It can be associated with fracture or dislocation about the shoulder or without obvious bone injury.

• Diagnosis includes:

  • Massive swelling of shoulder region

  • A pulseless arm

  • A complete or partial neurologic deficit

  • Lateral displacement of the scapula on a nonrotated chest radiograph, which is diagnostic (Fig. 13.7)

     

     

     

• Classification

  Type I: Musculoskeletal injury alone

  Type IIA: Musculoskeletal injury with vascular disruption

  Type IIB: Musculoskeletal injury with neurologic impairment

  Type III: Musculoskeletal injury with both neurologic and vascular injury

• Initial treatment

  • Patients are often polytraumatized.

  • Advanced trauma life support protocols should be followed.

  • Angiography of the limb with vascular repair and exploration of brachial plexus are performed

    as indicated.

  • Stabilization of associated bone or joint injuries is indicated.

• Later treatment

  • Neurologic

    • At 3 weeks, electromyography is indicated.

    • At 6 weeks, cervical myelography or magnetic resonance imaging (MRI) is performed.

    • Shoulder arthrodesis and/or above elbow amputation may be necessary if the limb is flail.

    • Nerve root avulsions and complete deficits have a poor prognosis.

    • Partial plexus injuries have good prognosis, and functional use of the extremity is often regained.

    • MRI—“empty sleeve sign”

  • Osseous

    • If initial exploration of the brachial plexus reveals a severe injury, primary above elbow amputation should be considered.

    • If cervical myelography reveals three or more pseudomeningoceles, the prognosis is similarly

      poor.

• This injury is associated with a poor outcome including flail extremity in 52%, early amputation in 21%, and death in 10%.

  Intrathoracic Dislocation of the Scapula

• This is extremely rare.

• The inferior angle of the scapula is locked in the intercostal space.

• Chest computed tomography may be needed to confirm the diagnosis.

• Treatment consists of closed reduction and immobilization with a sling and swathe for 2 weeks, followed by progressive functional use of the shoulder and arm.