MRI
A magnetic resonance imaging scan, or MRI, is used to see small changes in the body that cannot be seen with a normal x-ray. Magnets and radio waves are used to make a computer picture of the parts of the body the doctor wants to study.

If you have myositis, the doctor may study the affected muscles using an MRI to get a better picture of any muscle damage.  Read more...

EMG
An electromyogram, or EMG, is a test that measures the activity of the muscles. The test gathers information about the muscular and nervous systems.

An EMG is a way of finding causes of muscle weakness or paralysis; muscle problems such as muscle twitching; numbness, tingling or pain; and nerve damage or injury. Read more...