Arthrogram

It is used primarily in the evaluation of menisci, cruciate ligaments, articular cartilage, and loose body within a joint. Fluoroscopic allows general view of the medial, lateral, and patellofemoral ligaments of the joint, overall cartilage thickness, focal defects, imbibition (absorption} of contrast material into the articular cartilage (a sign of cartilage fibrillation - splaying and fraying of the cartilage).^[1]

CT arthrography is used to examine the patellofemoral joint.^[1]

MR sequences such as spin echo with T1 and T2-weighted sequences, inversion recovery, chemical shift selective techniques, and gradient echo techniques are used to examine the articular cartilage.^[1]

Shoulder arthrography can be used to study tears of the rotator cuff, glenoid labrum and biceps.^[2] The type of contrast injected into the joint depends on the subsequent imaging that is planned. For pneumoarthrography, gas is used, for CT or radiographs, a water-soluble radiopaque contrast, and for MRI, gadolinium. Double-contrast arthrography can be used for more anatomically complex cases, though its use is relatively infrequent. The needle is radiographically guided into the glenohumeral joint space, after which the patient is evaluated by fluoroscopy, CT or MRI. The gadolinium in the contrast fluid yields a bright signal on T1 weighted images allowing for better evaluation of the joint capsule, the articular surface of the bones and, in particular, the labral cartilage. MR arthrography is most often used in evaluation of the hip and acetabular labrum, of the shoulder rotator cuff and glenoid labrum, and less often in the wrist.^[2] Arthrograms can be diagnostic and therapeutic. Therapeutic arthrograms often distend the joint with cortisone and lidocaine, with a common site being the shoulder. Diagnostic arthrograms can be direct, as described above with penetration of the joint, or indirect, by a venous injection of contrast material and delayed imaging with CT or MRI.^[2]

Patients who are allergic to or sensitive to medications, contrast dyes, local anesthesia, iodine, or latex should not have this procedure. Potential risks are infections at the puncture site where the radiopaque substance and/or air are injected. Bleeding is also a small risk. Rarely, gadolinium, found in MRI contrast agents, can cause nephrogenic systemic fibrosis (NSF), a debilitating and potentially fatal disease affecting skin, muscle, and internal organs, in patients with impaired renal function.^[3]

• Medical Imaging
• Radiographer
• Radiologist

• FDA website on gadolinium-containing contrast agents
• Video tutorial for performing an arthrogram