Shoulder X-ray Interpretation in 4 Steps

Shoulder X-rays Interpretation steps include:

• Step 1: assess Bones
• Step 2: assess Joints
• Step 3: assess Soft tissue
• Step 4: assess Ribs and Lungs

Step 1: assess Bones

Trace the edges of the bones looking for cracks while assessing the bones in Shoulder X-rays interpretation

• Start with Humerus then clavicle, glenoid, coracoid, spine, acromion, scapula, subscapular fossa
• If you see the fracture then start with the fracture then look elsewhere
• Look at the general appearance of the bone looking for decrease or increase in density (osteopenia vs osteosclerosis) or abnormal trabeculation (Paget’s disease)
• Decrease in bone density in greater tuberosity of humerus is normal

Normal Shoulder X-ray; by Nevit Dilmen, via Wikimedia Commons

Normal Shoulder X-ray; by Nevit Dilmen, via Wikimedia Commons

Step 2: assess Joints

Assess:

• Glenohumeral joint
• Acromioclavicular joint
• Sternoclavicular joint

Look for the shape of the joint, congruity of the bone ends and look for narrowing or asymmetry

• Glenohumeral joint: overlap between humeral head and glenoid with articular surfaces almost replicating each other
• Acromioclavicular joint:
  • The inferior edge of the clavicle bone and inferior edge of the acromion should be leveled (on the same line) on clavicle AP view with 20 degree cephalic tilt
  • It is okay if the superior edges don’t match up
  • The joint space should be uniform and joint distance less than 8 mm (normal 5-8 mm)
  • Normal Coracoclavicular distance is between 11-13 mm and there should be no greater than 5 mm difference between right and left
• Sternoclavicular joint also checked if you can see it

Normal Shoulder X-ray; by Nevit Dilmen, via Wikimedia Commons

Normal Acromioclavicular jointNormal Acromioclavicular joint

Step 3: assess Soft tissue

Soft tissue refers to all soft tissues except lungs

• Look for changes in density, abnormal bulges or any obvious secondary signs of trauma
• Higher density soft tissues are muscles while lower density soft tissues are fat

Step 4: assess Ribs and Lungs

• Check the ribs looking for fractures
• Check lung field make sure they reach the rib cage (no pneumothorax)

Lateral Shoulder X-Rays

Same 4 steps applies to the lateral shoulder X-Rays

• Coracoid process always pointing anteriorly
• Humerus is sitting in the middle of the glenoid
• Lung fields going to the edges of rib cage

Normal Lateral Shoulder X-Rays; by Mikael Häggström, CC0, via Wikimedia Commons

Normal Lateral Shoulder X-Rays; by Mikael Häggström, CC0, via Wikimedia Commons

Axial Shoulder X-Rays

• Not easy to obtain on trauma patients (painful)
• Same 4 steps applies to the axial shoulder X-Rays
• Anatomy: acromion, humerus, coracoid, clavicle
• Coracoid always pointing anterior
• Make sure the Humeral head is sitting in the glenoid

Normal Axial Shoulder X-ray; by RSatUSZ, CC BY-SA 4.0, via Wikimedia Commons

Normal Axial Shoulder X-ray; by RSatUSZ, CC BY-SA 4.0, via Wikimedia Commons

Imaging Series

• Shoulder series
  • AP
  • Lateral
  • +/- Axial
• Clavicle series
  • AP
  • Axial
• SC joint series
  • AP
  • Axial
• AC joint series: not many AC series (unless it is a confirmed injury) are done so you going to use clavicle X ray or AP shoulder to assess AC
  • AP
  • +/- Axial

SC Joint X-Rays

• SC joint require AP and Axial to be evaluated
• Also requires knowing the symptomatic side
• Draw a line between your midclavicular plane for both views, so you can appreciate the displacement
• Axial very helpful in looking for displacement

Sternoclavicular joint dislocation and arthritis; by J. Christoph Katthagen, Dimitri S.Tahal, Travis J.Menge, Marilee P. Horan, Peter J.Millett, Public domain, via Wikimedia Commons

Sternoclavicular joint dislocation and arthritis; by J. Christoph Katthagen, Dimitri S.Tahal, Travis J.Menge, Marilee P. Horan, Peter J.Millett, Public domain, via Wikimedia Commons

Examples

• James Heilman, MD, CC BY-SA 3.0 <https://creativecommons.org/licenses/by-sa/3.0>, via Wikimedia Commons
• Bentplate, CC BY-SA 3.0 <https://creativecommons.org/licenses/by-sa/3.0>, via Wikimedia Commons
• Christophe Dang Ngoc Chan (cdang), CC BY-SA 3.0 <http://creativecommons.org/licenses/by-sa/3.0/>, via Wikimedia Commons
• Hellerhoff, CC BY-SA 4.0 <https://creativecommons.org/licenses/by-sa/4.0>, via Wikimedia Commons
• Mikael Häggström, M.D.Consent note: Written informed consent was obtained from the individual, including online publication., CC0, via Wikimedia Commons
• Mikael Häggström, M.D.Consent note: Written informed consent was obtained from the individual, including online publication., CC0, via Wikimedia Commons
• James Heilman, MD, CC BY-SA 3.0 <https://creativecommons.org/licenses/by-sa/3.0>, via Wikimedia Commons
• Thomas Zimmermann (THWZ), CC BY-SA 3.0 DE <https://creativecommons.org/licenses/by-sa/3.0/de/deed.en>, via Wikimedia Commons

Course Menu

This article is a part of the Shoulder and Arm Trauma Free Course, this course also contains:

• Course Introduction
• Clavicle Bone Fractures
• Scapula Bone Fractures
• Acromioclavicular Joint Injuries
• Sternoclavicular Joint Injuries
• Anterior Shoulder Dislocation
• Posterior Shoulder Dislocation
• Inferior Shoulder Dislocation
• Proximal Humerus Fractures
• Humeral Shaft fractures
• Shoulder X-ray Interpretation