Norwich Image Interpretation Course

Heidi Nunn (Advanced Practice Reporting Radiographer)

The Shoulder

Fracture prevalence Projections Normal paediatric anatomy Proximal humerus Clavicle Scapula Glenoid
Anterior dislocation Posterior dislocation Acromioclavicular joint subluxation Pseudo-subluxation Rotator cuff arthropathy Bone metastases Simple bone cyst

(hover over images to zoom, click to enlarge)
Learning outcomes
  • Assess skeletal radiographs using a systematic approach
  • Understand the different radiographic projections and how the anatomy changes with position
  • Understand what injuries will be demonstrated on different projections
  • Describe shoulder girdle anatomy
  • Understand mechanisms of injury and the likely fractures/dislocations which may result
  • Recognise less common fractures to the individual bones of the shoulder girdle
  • Accurately describe glenohumeral dislocations and associated fractures
  • Understand common eponyms
  • Recognise potential ligament injuries
  • Identify normal paediatric anatomy and the development of secondary ossification centres
  • Recognise common pathological conditions seen around the shoulder girdle
Fracture prevalence
  • A fall onto the shoulder tends to result in specific injuries depending on the general age of the patient:
Under 10 years
Fractured clavicle
15-40 years Acromioclavicular joint subluxation
Glenohumeral joint dislocation
Under 20 years and over 60 years Fractured proximal humerus
  • AP - then view image.

    The second image may be:
  • Supero-inferior axial or infero-superior axial if the AP is normal, and the patient can easily abduct their arm.
  • Modified axial, or lateral scapula "Y" view. The patient does not need to abduct their arm for these views and these projections can be easily obtained with the patient on a trolley.
Axial    Modified axial    Y view
Normal paediatric anatomy
  • In the unfused skeleton, the epiphyseal growth plate for the proximal humerus appears as two lucent lines. Commonly mistaken for fractures.
  • Also, secondary ossification centres are often seen at the acromion and the coracoid processes (images from same patient):
12 years
Normal paediatric shoulder
14 years
Normal paediatric shoulder
15 years
Normal paediatric shoulder
17 years
Normal paediatric shoulder
  • On the axial view, the ossification centre for the coracoid process may develop from the base or the tip. Both may simulate fractures:
Normal paediatric axial    Normal paediatric axial
Proximal humeral fractures
  • Humeral neck (anatomical and surgical), and greater tuberosity should be assessed carefully for evidence of:

    Break to the cortex
    Disruption to the trabecular pattern
    Sclerosis, suggesting impaction

Greater tuberosity, surgical neck fractures
  • In the paediatric skeleton, the proximal humeral metaphysis should be examined carefully for cortical disruption:

Metaphyseal fracture
    Metaphyseal fracture
  • Assess the whole radiograph (inc. ribs and lung), particularly injury due to high velocity, eg, RTA:
Clavicle, ribs, scapular fractures    Clavicle, ribs, scapular fractures
Clavicle fractures
  • Are usually easy to spot. If the fracture is minimally displaced and overlies the scapula/ribs, an angled up projection is helpful.
  • Fractures of the middle third of the clavicle are most common (especially in <20 year olds). Fractures of the lateral third are more likely to be seen in an older age group. Fractures of the medial third are uncommon.
Fractured clavicle, normal ossification centres
Scapula fractures
  • Will occur due to high velocity, eg, RTA.
  • Can be subtle due to overlying ribs/clavicle. If the mechanism of injury fits, then the scapula must be scrutinised, particularly the blade and spine of the scapula, and also the corocoid and acromion processes:
Fracture scapula blade
Glenoid fractures
  • Fractures to the anterior lip of the glenoid are usually very subtle and are therefore easily missed. They may occur due to direct trauma or following anterior dislocation.
Glenoid fracture
Anterior glenohumeral dislocation
  • Often occur due to sporting injuries.
  • Humeral head lies under the coracoid on the AP. On the axial it is displaced towards the coracoid. On the modified axial and lateral scapula "Y" view, humeral head is displaced towards the ribs/coracoid.
Anterior dislocation
  • Important to identify associated fractures. Common fractures involve:
    • the postero-lateral aspect of the humeral head (Hill-Sachs defect):
Anterior dislocation, Hill-Sachs defect    Anterior dislocation, Hill-Sachs defect
    • the anterior lip of the glenoid (Bankart lesion):
Anterior dislocation, Bankart lesion    Anterior dislocation, Bankart lesion    Post-reduction, Bankart lesion
    • the greater tuberosity:
Anterior dislocation, fracture greater tuberosity    Anterior dislocation, fracture greater tuberosity
Posterior glenohumeral dislocation
  • Tend to occur due to muscle spasm during epileptic fits, or electric shock.
  • The humerus is usually internally rotated, therefore the humeral head has a "light bulb" appearance on the AP. This is not always the case, however. There is widening of the joint (>6mm) as the humeral head is displaced laterally; this is called the rim sign. On the axial, the humeral head will be displaced towards the acromion/away from the ribs:
Posterior dislocation
  • Associated with avulsion fractures of the lesser tuberosity. Also, a medial and anterior humeral head compression fracture may be evident (trough line).
Acromioclavicular joint subluxation
  • Width of the normal joint is less than 7mm in adults. Widening indicates moderate sprain with rupture of the acromioclavicular ligament.
  • The inferior surfaces of the lateral clavicle and the acromion should be level. Subluxation is identified when the clavicle is elevated due to rupture of the coracoclavicular ligaments:
Wide ACJ    Subluxed ACJ    Dislocated ACJ
  • Blood within the joint causes inferior subluxation of the humeral head, however, this is not a true dislocation. Look for a possible underlying fracture:
Pseudosubluxation, fracture surgical neck
Rotator cuff arthropathy
  • Causes superior elevation of the humeral head, with reduction in the subacromial space, often with erosions developing on the inferior surface of the acromion. Causes impingement of the supraspinatus tendon. May occur in association with RA.
Rotator cuff tendonopathy
Bone metastases
  • Primary tumours often metastasise to the proximal humerus, and it is important to search for any moth-eaten, lytic lesions, or areas of sclerosis.
  • Potential lesions may be an incidental finding on a non-fractured humerus, or the fracture may be pathological in origin:
Bony metastases
Simple/Solitary/Unicameral bone cyst
  • A benign lytic lesion that is often seen at the diametaphyseal region of the proximal humerus. Again, may be an incidental finding, however, will sometimes fracture.
  • "Falling fragment sign" is sometimes seen, which refers to cortical fragments from the fracture, which fall through the fluid-filled lesion:
Solitary bone cyst


- return to top -