What is a spasm?

A spasm is defined as a sustained, involuntary muscular contraction. This means that the muscle involuntarily tightens and remains contracted, often leading to pain and discomfort. Muscle spasms can occur due to various factors such as overuse, dehydration, or muscle strain. They can manifest in different muscles in the body and can vary in duration and intensity.

The other options describe different conditions or injuries related to muscles and joints, but they do not accurately represent what a spasm is. For example, a painful injury to a joint refers to a specific type of injury rather than a muscular condition. An excessive stretch of muscle fibers describes a muscle strain, while a muscle tear indicates a more severe injury to the muscle tissue itself. Understanding these distinctions is crucial in differentiating various muscular and joint-related issues.