Glenohumeral arthrography

Glenohumeral (shoulder) arthrography is an imaging technique used to evaluate the glenohumeral joint to evaluate the joint components. A glenohumeral joint injection is usually performed under fluoroscopic guidance although ultrasound ¹ andand CT can be also be used. An alternative to direct arthrography (where contrast is injected into the joint) is indirect arthrography.

Historically arthrograms were performed with fluoroscopy and plain radiographs only. Today all patients proceed to cross-sectional shoulder imaging after contrast injection. This is usually MRI but CT is sometimes performed if there are contraindications to MR or if there is high suspicion of an associated bony abnormality.

Indications

• shoulder instability
• to assess joint structures
  • rotator cuff
  • glenohumeral articular cartilage
  • glenoid labrum

Procedure

For direct arthrography, a glenohumeral joint injection is carried out commonly under fluoroscopy or CT guidance, although ultrasound guidance can also be used ¹. The arthrographic contrast will depend on whether CT or MRI arthrography is being carried out. 

CT injectate

Iodinated contrast with a concentration of no more than 240 mg of Iodineiodine per mlmL ⁵. 

MR injectate

A very dilute (1/200 to 1/250) solution of gadolinium-containing MRI contrast agent is used in sterile saline (reaching a concentration of 0.0020–0.0025 mmol/ml/mL) ⁵. Some centres may use a mixture of normal saline and local anaesthetic as this has been shown to reduce artifact and periprocedural pain ⁶. A typical solution may be (but this will vary by institution) ⁷:

• 0.1 mL gadolinium MRI contrast agent
• 10 mL local anaesthetic (e.g. 0.5% ropivacaine)
• 10 mL normal saline

The glenohumeral joint capacity is 8-15 mL, although a 12 mL intra-articular injection of the above 20 mL solution is typically adequate for joint distension ^5,7.

If injected fluoroscopically or under CT guidance, then a small amountvolume (1-3 mL) of dilute iodinated contrast can also be injected first to confirm intra-articular position⁷.