Creatine Kinase is a type of protein that is mostly found in the skeletal muscle (CK-MM). 97 to 100% of Creatine Kinase are usually found in skeletal muscle. The other two types of Creatine Kinase are CK-MB (Creatine Kinase found in the heart muscle) and CK-BB (Creatine Kinase found in brain tissue).
Skeletal muscles are the muscles attached to your skeleton. They work with your bones to help you move and give your body power and strength. Heart muscles pump blood in and out of the heart.
CK-MM isoenzyme makes up almost all the circulatory total CK in the healthy person.
A CK test is most often used to diagnose and monitor muscular injuries and diseases.
These diseases include:
- Muscular dystrophy, a rare inherited disease that causes weakness, breakdown, and loss of function of skeletal muscles. It mostly occurs in males.
- Rhabdomyolis, a rapid breakdown of muscle tissue. It can be caused by a serious injury, muscle disease, or other disorder.
The test can be used to help diagnose a heart attack, though not very often. Another test, called troponin, has been found to be better at detecting heart damage.
CK-MM
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