•Arthrography is a medical imaging procedure which is performed to demonstrate and assess the joint and associated soft tissue structures for pathologic processes.
• These structures are visualized through the introduction of a contrast agent into the joint capsule.
•Joints studied include the hip, knee, ankle, shoulder, elbow, wrist, and temporomandibular joints (TMJs).
Structures of Major Interest in Shoulder
•The joint capsule
•long tendon of the bicep muscle and articular cartilage
Structures of Major Interest in Ankle
•The joint capsule
•menisci and collateral cruciate ligament And other minor ligaments of the ankle
•structures of Major Interest Wrist
•The joint capsule; menisci, scapholunate ligament, lunotriquetral ligament, and the triangular fibrocartilage complex, additional intrinsic and extrinsic ligaments.
•The Primary indications for an arthrography procedure are trauma, persistent pain, and limitation of motion resulting from any of the following conditions Condition Radiographic Finding
•Dislocation – displacement of a bone from a joint
•Joint Capsule Tear– Rupture of the joint capsule
•Ligament Tear– Rupture of the ligament
•Meniscus Tear– Rupture of the meniscus
•Rotator Cuff Tear– Rupture of any muscle of the rotator cuff
•Explain the procedure to the patient thoroughly before the examination to preclude patient anxiety.
•Advise the patient of any possible complications involved with doing the procedure.
•Patient must provide information on allergies, medication and possible pregnancy prior to the procedure.
•Patient must sign an informed consent form before the procedure is done.
•Conventionally, image acquisition is obtained using fluoroscopy. However, CT and MRI have largely replaced this. However, fluoroscopic imaging may be used in conjunction with these imaging modalities.
•The contrast media is injected under fluoroscopic guidance and the joint is manipulated with spot films being taken to ensure the area of interest is demonstrated by the contrast media.
• After the joint has been adequately evaluated under fluoroscopy, the patient is transferred to CT or MRI for further imaging.
•The exact protocol and procedure for CT or MRI arthrography depends on the area of interest being examined and the protocol of the facility or physician.
•Radiolucent (negative) agent; and radiopaque (positive) iodinated, water-soluble agent (omnipaque 300) is used for CT and fluoroscopic arthrography.
•Gadolinium is used for MR arthrography.
•Contrast media may be introduced to the body indirectly, where it is injected into the bloodstream and eventually absorbed into the joint, or directly, where it is injected into the joint space.
NEEDLE PLACEMENT AND INJECTION PROCESS
the patient is in the supine position with the shoulder slightly externally rotated.
Skin entry site is at the junction of the middle and inferior thirds of the humeral head medial aspect, 2mm inside the cortex.
After the area is anesthetized, fluoroscopy is used to guide the needle into the joint space with a spinal needle.
A small amount of contrast media is injected to determine whether the bursa has been penetrated. When the contrast media has been fully instilled, imaging begins.
The patient is in the AP position with the ankle rotated 90° laterally.
Skin entry site is medial to the anterior tibial or medial to the extensor hallucis longus tendon. The dorsalis pedis artery should be avoided, and its path should be marked on the skin.
After the area is anesthetized, under fluoroscopy the needle is placed slightly cranial beneath the anterior lip of the tibia, and is advanced until its tip is between the tibia and the talus.
Before the joint injection of iodinated contrast media, aspiration is performed to confirm correct position and to avoid dilution of the contrast media. The contrast solution is used to distend the joint capsule and observe the contrast agent distribution within the articular space.
The patient is in the prone position with the wrist pronated.
Wrist arthrography can be performed using: a single-compartment (radiocarpal), double-compartment (radiocarpal and midcarpal or radiocarpal and distal radioulnar), or triple-compartment (midcarpal, radiocarpal, and distal radioulnar joint (DRUJ) injection technique.
The joint is then manipulated under fluoroscopy to spread the contrast media and demonstrate the exact area of leakage.
Midcarpal Joint Injection
•The needle’s target for the midcarpal compartment is the scaphocapitate and triquetrohamate spaces. A 25-gauge needle is usually placed at the triquetrolunohamate space from a dorsal approach, and the injection is carried on until the contrast medium flows in the capitolunate joint compartment.
Radiocarpal Joint Injection
•The injection is at an anatomic sulcus between the extensor pollicis longus and the index finger extensor digitorum communis tendon. The puncture site is ∼0.5 cm below the dorsal lip of the radius so that the needle angulation (10°-15° ) is parallel to the distal radial articular surface.
•For radiocarpal ulnar-sided injection, the needle is advanced from the proximal border of the triquetrum to the pisiform radial edge. For radial-sided injection, the needle’s target is instead the radioscaphoid space through the scapholunate joint.
Distal Radioulnar Joint (DRUJ) Injection
•The needle is directed near the radial border of ulnar head. When the needle reaches the ulnar head, it is inserted deeper into the center of the joint space.
•Triple-compartment arthrography is performed first with a midcarpal joint injection of 3 to 4 mL of contrast medium. If a communication between midcarpal and radiocarpal is present, an additional 3 to 4 mL is injected, and if a communication with the DRUJ occurs, supplementary 1 to 2 mL is added for a total of 7 to 9 mL.
•If no communication is present, the radiocarpal and DRUJ are sequentially injected with 3 to 4 mL and 1 to 2 mL of contrast medium, respectively.
Positioning & Imaging Sequence Shoulder
•Imaging can be done with the patient upright or supine.
•In fluoroscopy the projections often used are: AP (internal & external rotation); glenoid fossa, transaxillary, intertubercular (bicipital) groove.
•Scout images are performed and then repeated after the contrast agent has been injected. If the radiographs appear normal, the patient is directed to exercise the shoulder, and the radiographs are repeated. This is followed up with CT or MRI imaging.
•Imaging is done with the patient supine.
•In Fluoroscopy the projections used are: AP, lateral, internal and external oblique views
•If the capsule is intact passive and exercises are performed while imaging.
•This is followed by imaging with either CT or MRI.
•the projections used at typically the PA, as well as PA with ulnar and radial deviation, lateral and both obliques. Digital Subtraction techniques are also available with some systems to improve visualization of the joint spaces. This is performed in conjunction with CT and MRI arthrography
POST PROCEDURE CARE
•Rest the joint that was injected for at least 12 hours after the procedure.
• Ice packs or over the counter pain relief medication is recommended to decrease pain and swelling.
• Symptoms of pain, red skin or fever 3 or more days following the procedure should be reported to your physician.
RISK ASSOCIATED WITH THE PROCEDURE
•Any procedure where the skin is penetrated carries a risk of infection. The chance of infection requiring antibiotic treatment is significantly low
•There is the possibility of injuring a vessel or a nerve adjacent to the joint. Injury to these structures, however, is minimal particularly when the procedure is performed under imaging guidance.
• Patients who have known allergies to iodine may have an adverse reaction to the contrast material. Because the contrast material is put in a joint and not a vein, allergic reactions are very rare, although in some cases, mild nausea to severe cardiovascular complications may result.
•There is always a slight chance of cancer from excessive exposure to radiation. However, the benefit of an accurate diagnosis far outweighs the risk.
•Bontrager, K., & Lampignano, J. (2014). Special Radiographic Procedures. In Workbook for Textbook of radiographic positioning and related anatomy, (8th ed., pp. 715-719). St. Louis, Mo.: Elsevier Mosby.
• Dalinka, M. (2011). Arthrography. S.l.: Springer.
• Masala, S., Fiori, R., Bartolucci, D., Mammucari, M., Angelopoulos, G., Massari, F., & Simonetti, G. (2010). Diagnostic and Therapeutic Joint Injections. Semin Intervent Radiol Seminars in Interventional Radiology, 27(2), 160-171. doi:10.1055/s-0030-1253514