(Joint X-ray, Arthrogram)
What is arthrography?
Arthrography is a type of X-ray used to examine a joint, such as the knee or hip, when standard Xrays are not adequate. A series of X-rays is taken with the joint in various positions after contrast dye is placed in the joint. An arthrogram may use fluoroscopy, CT, or MR imaging to better visualize the joint.
While arthrography is most commonly used to examine the knee and shoulder joints, it may also be used to examine other joints, such as the wrist, ankle, hip, or elbow.
Anatomy of the shoulder
The shoulder is made up of several components, including the following:
Bones. These are the collarbone (clavicle), the shoulder blade (scapula), and the upper arm bone (humerus).
Joints. These facilitate movement, including the acromioclavicular (AC) joint (where the clavicle meets the acromion) and the shoulder joint (glenohumeral joint) that facilitates forward, circular, and backward movement of the shoulder.
Ligament. A type of tough, elastic connective tissue that surrounds the joint to give support and limits the joint's movement. The ligaments of the shoulder include the joint capsule (a group of ligaments that connect the humerus to the socket of the shoulder joint on the scapula to stabilize the shoulder and keep it from dislocating), ligaments that attach the clavicle to the acromion, and ligaments that connect the clavicle to the scapula by attaching to the coracoid process.
Acromion. This is the roof (highest point) of the shoulder that is formed by a part of the scapula.
Tendon. A type of tough connective tissue that connects muscles to bones and helps to control movement of the joint.
Muscle. A strong, contractile tissue that helps support and rotate the shoulder in many directions.
Rotator cuff. Composed of tendons, the rotator cuff (and associated muscles) holds the ball of the glenohumeral joint at the top of the upper arm bone (humerus).
Bursa. A fluid-filled sac located between bones, ligaments, or other adjacent structures that helps cushion joints. In the shoulder, the bursa is located between the rotator cuff muscle layer and the outer layer of large, bulky muscles and keeps the rotator cuff from rubbing on the shoulder joint.
Anatomy of the knee
The knee is a vulnerable joint that bears a great deal of stress from everyday activities, such as lifting and kneeling, and from high-impact activities such as jogging and aerobics.
The following parts form the knee:
Tibia. This is the shin bone or larger bone of the lower leg.
Femur. This is the thighbone or upper leg bone.
Patella. This is the kneecap.
Each bone end is covered with a layer of cartilage that absorbs shock and protects the knee. Basically, the knee is two long leg bones held together by muscles, ligaments, and tendons.
There are two groups of muscles involved in the knee, including the quadriceps muscles (located on the front of the thighs), which straighten the legs, and the hamstring muscles (located on the back of the thighs), which bend the leg at the knee.
Tendons are tough cords of tissue that connect muscles to bones. Ligaments are elastic bands of tissue that connect bone to bone. Some ligaments of the knee provide stability and protection of the joints, while other ligaments limit forward and backward movement of the tibia (shin bone).
Reasons for the procedure
Arthrography may be performed on a joint when there has been persistent and unexplained pain, discomfort, and/or dysfunction in the joint. Other reasons to perform arthrography may include, but are not limited to, the following:
To identify abnormalities (for example, acute and chronic tears) in the soft tissues of the joint, such as ligaments, cartilage, and joint capsules
To evaluate damage from recurrent dislocations of the joint
To visualize synovial cysts
There may be other reasons for your doctor to recommend arthrography.
Risks of the procedure
You may want to ask your doctor about the amount of radiation used during the procedure and the risks related to your particular situation. It is a good idea to keep a record of your past history of radiation exposure, such as previous scans and other types of X-rays, so that you can inform your doctor. Risks associated with radiation exposure may be related to the cumulative number of X-ray examinations and/or treatments over a long period of time.