Muscle weakness and myalgia. MR imaging investigation.

The status of muscle integrity need no longer be surmised on the basis of gross clinical assessments of muscle strength and invasive procedures. MR imaging brings to the clinical arena new capabilities to aid the management of patients with common muscle complaints of common and uncommon causes. Although findings on MR imaging tend to be nonspecific, muscle structural lesions can be defined in terms of extent and gross composition, and thus help direct invasive procedures and monitor therapies. Radiologists need to remember that their observation of muscle lesions on MR imaging may be the serendipitous discovery of the true cause of a patient's compliant.