Radiography of the Shoulder Jennifer Nicol PGY-1 August 6, 2009

Objectives BRIEF Anatomy Review Standard shoulder views Radiographs of shoulder injuries NOT: ◦ Treatment ◦ Other imaging modalities ◦ Pediatric imaging

Anatomy

Shoulder Views Over 15 views of shoulder described Trauma series: ◦ 3 views:  AP  Trans-scapular “Y-view”  Axillary  Modified axillary

AP view True AP - 45˚tilt ◦ Glenohumeral joint with no bony overlap ◦ Preferred in trauma AP int/ext rotation ◦ Highlight tuberosities ◦ Soft tissue injuries Clavicle and AC joint

Transcapular view Projects along long axis scapula Simple, reproducible Good for visualising anterior, posterior dislocations

Acromion Coracoid Body

Axillary View Glenohumeral joint in cephalocaudal plane Lesions of glenoid rim, humeral head, caracoid Axial view of shoulder

Modified Axillary View Reverse axillary when pt can’t abduct

Retrospective 1690 shoulder exams ◦ Mod axillary view used 104 times ◦ Identified additional pathology in 30 cases No comparison b/t standard and modified axillary

Approach to Shoulder XR AP: ◦ If ext/int rotation look at tuberosity orientation ◦ Glenohumeral region  Alignment  Distance b/t humeral head and glenoid  Bones ◦ AC region ◦ Other regions (clavicle, ribs, scapular spine,lungs)

Approach to Shoulder XR Other views: ◦ Humeral head to glenoid ◦ Prox humerus ◦ Glenoid rim ◦ Scapula ◦ Carocoid ◦ Acromion

1)Glenoid Alignment Distance bones 2)AC Alignment Carocoid-clavicle space 3)Other Lungs, scapula, ribs, clavicle Type I AC injury

Type III AC injury

Posterior Dislocation

Positive Rim Sign

Trough Sign

No Mercedes!!!!

Avulsion Lesser Tuberosity

Bilateral shoulder dislocation spontaneously reduced with bilateral reverse Hill-Sachs lesions

Posterior Dislocations Have high suspicion with correct mechanism Don’t miss – clinical exam important Look for associated fractures Types: ◦ Subacromial (98%) ◦ Subglenoid ◦ subspinosus

Anterior Dislocation

Scapular View: Anterior Dislocation

Hill-Sachs deformity

AP Bankhart Injury Axillary

Greater Tuberosity Fracture

Anterior Dislocations 4 Types ◦ Subcoracoid ◦ Subglenoid ◦ Subclavicular ◦ Intrathoracic

Anterior Dislocations Check Neurovascular exam pre-post reduction Don’t delay reduction – NV injury increases with time Recurrence high – 80% <30

Inferior Dislocation

Subglenoid anterior dislocation

Pseudodislocation