Muscle strength function tests . Beyond physical tests, certain diagnostic procedures offer excellent images to diagnose soft-tissue trauma. MRI is the imaging test most commonly used in the United States to diagnose soft-tissue injuries. Ultrasound is less stressful and less expensive than MRI, but is used less often because it requires special skill in analysis. It can, however, provide an accurate picture adequate for diagnosis if the examining physician is experienced in ultrasound interpretation.
Some tests involve equipment in a sports laboratory.
For example, a procedure called the KT-1000 uses a machine that tests injured knee ligaments with the application of force. The knee joint is moved back and forth while its motion is analyzed and compared with that of the normal knee joint. Other sports lab tests include the Kincom test for muscle strength and a video analysis of the gait to determine if a change in running style will prevent future stress fractures. Under certain circumstances, a more invasive procedure may be necessary to confirm diagnosis of a soft-tissue injury. With the use of portable equipment and disposable arthroscopes, this procedure can be performed in some doctors' offices under local anesthetic.