Anatomy

  • Scapula does not have any bony connection to the thorax and serves primarily for muscle attachments
  • Serves as origin for the deltoid muscle, providing leverage for the primary movements of the shoulder

Epidemiology (Wheeless 2018)

  • Uncommon
    • less than 1% of all fractures
    • 3% of shoulder fractures (Murphy 2018)
  • Fractures of the body and spine account for about 50% of scapular fractures

Mechanism of Injury

  • Scapular fractures associated with high energy trauma
    • MVCs account for 50% of scapular fractures (Murphy 2018)
    • Falls from heights
  • Direct trauma to shoulder
  • Indirect trauma by FOOSH
  • Non-accidental trauma in children
  • Identification of scapular fracture should raise concern for further injury

Concomitant Injuries (Wheeless 2018)

  • Concomitant injuries occur in 80-90% of patients
  • 2-5% mortality rate, usually secondary to associated pulmonary or head trauma
  • Associated with high Injury Severity Scores
  • Associated Orthopedic Injuries
    • Rib fractures (52%)
    • Spine fracture (29%)
    • Clavicle fracture (23%)
    • Brachial plexus injury (5%)
  • Associated Non-Orthopedic Injuries
    • Pulmonary contusion (41%)
    • Head injury (34%)
    • Pneumothorax (23-32%)
    • Vascular injury (11%), commonly axillary artery injury
      • Association with blunt aortic injury may be overestimated

Glenoid Fractures (orthobullets.com)

Types of Scapular Fractures (Weatherford 2018)

  • Scapular Body Fractures (~50%)
    • Fractures described based on anatomic location
  • Scapular Neck Fractures (~25%)
    • Type I: Fracture of neck without associated clavicle fracture or AC joint dislocation
    • Type II: Fracture of neck with associated clavicle fracture and AC joint separation
  • Gelnoid Fractures (~10%)
    • Type I
      • Type Ia: Anterior rim fracture
      • Type Ib: Posterior rim fracture
    • Type II: Fracture line through glenoid fossa exiting scapula laterally
    • Type III: Fracture line through glenoid fossa exiting scapula superiorly
    • Type IV: Fracture line through glenoid fossa exiting scapula medially
    • Type V
      • Type Va: Combination of types II and IV
      • Type Vb: Combination of types III and IV
      • Type Vc: Combination of types II, III, and IV
    • Type VI: Severe comminution

  • Acromion Fractures (orthobullets.com)

    Acromial Fractures (~ 8%)

    • Type I: Nondisplaced or minimally displaced (IA: avulsion; IB: complete fracture)
    • Type II: Displaced but does not reduce the subacromial space
    • Type III: Displaced and reduces the subacromial space
  • Coracoid Fractures (~ 7%)
    • Type I: Displaced and reduces the subacromial space
    • Type II: Fracture occurs toward the tip of the coracoid

Coracoid Fractures (orthobullets.com)

Scapula Body Fracture (Case courtesy of Mr Andrew Murphy, Radiopaedia.org. From the case rID: 45880)

Diagnostic Imaging

  • Plain radiograph – recommended views
    • True AP view of the scapula
    • Lateral view
    • Axillary view
  • CT
    • Obtain CT Chest in patients with scapular fracture following blunt chest trauma
    • Standard for diagnosis and evaluation of the fracture and associated injuries
    • Particularly useful in evaluation of intra-articular glenoid fractures
    • 3D reconstruction can be helpful

Scapula Fractures (www.orthobullets.com)

 

Acromion Fracture (Case courtesy of Dr Maulik S Patel, Radiopaedia.org. From the case rID: 30094)

CT Scapula Body Fracture (Radiopaedia.org. From the case rID: 28072)