Arthrogram
Encyclopedia
An arthrogram is a series of images, often X-rays, of a joint
after injection
of a contrast medium
. The injection is normally done under a local anesthetic
.The radiologist performs the study utilizing fluoroscopy
or ultrasound
to guide the placement of the needle into the joint and then injects an appropriate quantity of contrast.
(CT) scans or Magnetic resonance imaging
(MRI) scans. The joint can be imaged from many angles in fluoroscopy, or on a slice by slice basis in CT and MRI scans.
Shoulder arthrography can be used to study tears of the rotator cuff
. The procedure can also define abnormalities of the glenoid labrum and bicipital
tendon and sheath.
For pneumoarthrography, a gaseous medium has been used, for opaque arthrography a water-soluble iodinated medium is used, and a combination of both has been used in double-contrast arthrography. Current practice is single contrast arthrography usually coupled with CT or MR imaging.
The exam is usually done under the fluoroscope, or less commonly ultrasound, to guide the needle into the correct place in the joint.
Increasingly utilized in the last ten years, Magnetic Resonance Arthrography and Computed tomography arthrography (CT) combines a standard arthrogram with Magnetic Resonance Imaging or CT scanning. While preparing the iodine contrast for injection into the joint, the physician adds a small quantity (usually less than 1 ml) of gadolinium
contrast. Once the joint has been injected, the traditional radiographic images may or may not be obtained, and the patient then undergoes an MR or CT of the joint. The gadolinium in the contrast fluid yields a bright hyperintense signal on T1 weighted images and allows evaluation of quite small defects of the joint capsule, the articular
surface of the bones and of 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.
Arthrograms, in practice, can be diagnostic or therapeutic. Therapeutic arthrograms are often joint distention and cortisone injection procedures. A frequent site for such a procedure is 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 later imaging with CT or MRI.
Reports have arisen of gadolinium contrast agents causing nephrogenic systemic fibrosis
(NSF), a debilitating and potentially fatal disease affecting skin, muscle, and internal organs. These cases have only occurred in people with moderate-to-end-stage kidney disease; there have been zero reports of gadolinium leading to health problems in individuals with healthy kidneys. The mechanism linking gadolinium, kidney dysfunction, and NSF is currently unknown. The U.S. Food and Drug Administration (FDA) has recommended that physicians refrain from using gadolinium contrast agents on patients with kidney disease "unless the diagnostic information is essential and can not be obtained with non-contrast-enhanced MRI or other diagnostic procedures."
Aside from the risk of NSF in people with kidney disease, arthrograms carry the same risks as ordinary X-ray
s or MRI scans.
Joint
A joint is the location at which two or more bones make contact. They are constructed to allow movement and provide mechanical support, and are classified structurally and functionally.-Classification:...
after injection
Injection (medicine)
An injection is an infusion method of putting fluid into the body, usually with a hollow needle and a syringe which is pierced through the skin to a sufficient depth for the material to be forced into the body...
of a contrast medium
Contrast medium
A medical contrast medium is a substance used to enhance the contrast of structures or fluids within the body in medical imaging...
. The injection is normally done under a local anesthetic
Local anesthetic
A local anesthetic is a drug that causes reversible local anesthesia, generally for the aim of having local analgesic effect, that is, inducing absence of pain sensation, although other local senses are often affected as well...
.The radiologist performs the study utilizing fluoroscopy
Fluoroscopy
Fluoroscopy is an imaging technique commonly used by physicians to obtain real-time moving images of the internal structures of a patient through the use of a fluoroscope. In its simplest form, a fluoroscope consists of an X-ray source and fluorescent screen between which a patient is placed...
or ultrasound
Medical ultrasonography
Diagnostic sonography is an ultrasound-based diagnostic imaging technique used for visualizing subcutaneous body structures including tendons, muscles, joints, vessels and internal organs for possible pathology or lesions...
to guide the placement of the needle into the joint and then injects an appropriate quantity of contrast.
Related technologies
The physician or technologist then obtains a series of X-rays, or alternatively computerized tomographyComputed tomography
X-ray computed tomography or Computer tomography , is a medical imaging method employing tomography created by computer processing...
(CT) scans or Magnetic resonance imaging
Magnetic resonance imaging
Magnetic resonance imaging , nuclear magnetic resonance imaging , or magnetic resonance tomography is a medical imaging technique used in radiology to visualize detailed internal structures...
(MRI) scans. The joint can be imaged from many angles in fluoroscopy, or on a slice by slice basis in CT and MRI scans.
Use
The physician assesses the images produced.Shoulder arthrography can be used to study tears of the rotator cuff
Rotator cuff tear
Rotator cuff tears are tears of one or more of the four tendons of the rotator cuff muscles. A rotator cuff injury can include any type of irritation or damage to the rotator cuff muscles or tendons....
. The procedure can also define abnormalities of the glenoid labrum and bicipital
Biceps brachii muscle
In human anatomy, the biceps brachii, or simply biceps in common parlance, is, as the name implies, a two-headed muscle located on the upper arm. Both heads arise on the scapula and join to form a single muscle belly which is attached to the upper forearm...
tendon and sheath.
For pneumoarthrography, a gaseous medium has been used, for opaque arthrography a water-soluble iodinated medium is used, and a combination of both has been used in double-contrast arthrography. Current practice is single contrast arthrography usually coupled with CT or MR imaging.
The exam is usually done under the fluoroscope, or less commonly ultrasound, to guide the needle into the correct place in the joint.
Increasingly utilized in the last ten years, Magnetic Resonance Arthrography and Computed tomography arthrography (CT) combines a standard arthrogram with Magnetic Resonance Imaging or CT scanning. While preparing the iodine contrast for injection into the joint, the physician adds a small quantity (usually less than 1 ml) of gadolinium
Gadolinium
Gadolinium is a chemical element with the symbol Gd and atomic number 64. It is a silvery-white, malleable and ductile rare-earth metal. It is found in nature only in combined form. Gadolinium was first detected spectroscopically in 1880 by de Marignac who separated its oxide and is credited with...
contrast. Once the joint has been injected, the traditional radiographic images may or may not be obtained, and the patient then undergoes an MR or CT of the joint. The gadolinium in the contrast fluid yields a bright hyperintense signal on T1 weighted images and allows evaluation of quite small defects of the joint capsule, the articular
Joint
A joint is the location at which two or more bones make contact. They are constructed to allow movement and provide mechanical support, and are classified structurally and functionally.-Classification:...
surface of the bones and of the labral cartilage. MR arthrography is most often used in evaluation of the hip and acetabular labrum
Acetabular labrum
The acetabular labrum is a ring of cartilage that surrounds the acetabulum ....
, of the shoulder rotator cuff
Rotator cuff
In anatomy, the rotator cuff is the group of muscles and their tendons that act to stabilize the shoulder. The four muscles of the rotator cuff, along with the teres major muscle, the coracobrachialis muscle and the deltoid, make up the seven scapulohumeral muscles of the human body.-Function:The...
and glenoid labrum, and less often in the wrist.
Arthrograms, in practice, can be diagnostic or therapeutic. Therapeutic arthrograms are often joint distention and cortisone injection procedures. A frequent site for such a procedure is 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 later imaging with CT or MRI.
Risks
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.Reports have arisen of gadolinium contrast agents causing nephrogenic systemic fibrosis
Nephrogenic systemic fibrosis
Nephrogenic systemic fibrosis or nephrogenic fibrosing dermopathy is a rare and serious syndrome that involves fibrosis of skin, joints, eyes, and internal organs. Its cause is not fully understood...
(NSF), a debilitating and potentially fatal disease affecting skin, muscle, and internal organs. These cases have only occurred in people with moderate-to-end-stage kidney disease; there have been zero reports of gadolinium leading to health problems in individuals with healthy kidneys. The mechanism linking gadolinium, kidney dysfunction, and NSF is currently unknown. The U.S. Food and Drug Administration (FDA) has recommended that physicians refrain from using gadolinium contrast agents on patients with kidney disease "unless the diagnostic information is essential and can not be obtained with non-contrast-enhanced MRI or other diagnostic procedures."
Aside from the risk of NSF in people with kidney disease, arthrograms carry the same risks as ordinary X-ray
X-ray
X-radiation is a form of electromagnetic radiation. X-rays have a wavelength in the range of 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz and energies in the range 120 eV to 120 keV. They are shorter in wavelength than UV rays and longer than gamma...
s or MRI scans.