I have a constant muscle spasm in my left buttock, there is no pain at all, and i had it for at least a week? what and why and how to get rid of it?

Muscle Spasm: Muscle spasm can be due to many causes. It can be an electrolyte disturbance, over-activity, nerve irritation and many others. The usual care for any acute injury is rest, ice, and mild stretching. Injuries to muscles usually heal pretty well and quickly. If any muscle issues are present for more than a few weeks, a more in-depth evaluation maybe necessary to identify the cause.