Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.
Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.
As we normally use our muscles, they alternately
contract and relax as we move our limbs back and forth. Similarly, the muscles
that maintain our posture contract and relax in a synchronized fashion. A muscle
that involuntarily contracts without our consciously willing it is called a
"spasm." If the spasm is forceful and sustained, it becomes a cramp. A muscle
cramp is an involuntarily and forcibly contracted muscle that does not relax.
Muscle cramps cause a visible or palpable hardening of the involved muscle.
Muscle cramps can last anywhere from a few seconds to a quarter of an hour or
occasionally longer. It is not uncommon for a cramp to recur multiple times
until it finally goes away. The cramp may involve a part of a muscle, the entire
muscle, or several muscles that usually act together, such as those that flex
adjacent fingers. Some cramps involve the simultaneous contraction of muscles
that ordinarily move body parts in opposite directions.
Muscle cramps are
extremely common, and nearly everyone experiences a cramp at some time in their
life. Cramps are common in adults and become increasingly frequent with aging.
However, children also experience cramps.
Any of the muscles that are under our
voluntary control (skeletal muscles) can cramp. Cramps of the extremities,
especially the legs and feet, and most particularly the calf (the classic
"charley horse"), are very common. Involuntary muscles, those we cannot control,
of the various organs (heart, uterus, blood vessel wall, intestinal tract, bile
and urine passages, bronchial tree, etc.) are also subject to spasms and cramps
but will not be further considered in this review. This article focuses on
cramps of the muscles that move joints, the muscles we can consciously control,
the voluntary muscle known as skeletal muscle.