An Arthrogram exam evaluates the internal part of you joint (called soft tissue). Many conditions such as arthritis, injuries, or infections can damage these parts. There is not special preparation for the test. The test takes about 1 hour. You will be asked to lie on a flat table. The radiologist will inject a medicine to numb you joint area. A second injection of clear liquid and/or air will be given to help show the soft tissue of the joint. Several x-rays will then be taken. After the x-rays are reviewed by the radiologist, you may leave the department.