Muscle Injuries on the Job

People with physically demanding jobs are often dealing with minor aches and pains, joint stiffness, and muscle injuries.  Many people don’t report minor injuries, like muscle strains, for several reasons; however, a lot of folks will later discover that their injury is not healing on its own and they need to get medical care.  Muscle injuries are commonly not reported until several days or weeks after the initial injury putting the injured worker at greater risk of having their claim denied.  Remember, you should always report work injuries right away.

What is a muscle strain?

Your muscles are responsible for all of the movements of your body. A muscle strain, more commonly called a “pulled” or “torn” muscle, is an injury where the muscle actually tears or rips. Usually, a muscle tear is unpredictable and it happens when the muscle is stretched too fast. Most often it occurs while the muscle is working, such as when running, working, or playing a sport. When the muscle tears, it usually hurts and causes the inability to continue the activity.

What happens when a muscle is strained?

When a muscle is strained, its softer part (called “muscle fibers”) stretch and pull and can even tear apart. Muscle strains most commonly occur where the muscle becomes a tendon, the so-called muscle-tendon junction. For example, the gastrocnemius muscle in your calf will frequently rupture at its junction with the Achilles tendon. When this junction is disrupted, the muscle stretches away from, or even detaches from, the tendon and can no longer create enough power to move the bone.                           

A muscle strain is more likely to happen to a muscle that is weak, inflexible, tired, or in one that has not been properly warmed up before exercise. Muscle strains often occur in athletes engaging in high speed activities, such as sprinters, where hamstring injuries are common. Other common areas for muscle injuries are groin muscles in soccer and chest muscles in weight lifters.

How will I know if I strained a muscle?

The signs of a muscle strain depend upon how severe the injury is to the muscle. In general, when it tears, there is a sudden onset of pain and you will know that you have had an injury. Muscle strains are graded as mild (first degree), moderate (second degree), or severe (third degree). A mild strain involves mostly stretching and limited tearing of the muscle fibers. It feels like the muscle is “knotted up.” There is some discomfort when you use the muscle but there is usually little loss of strength. A person with a mild strain can often continue activity but may have some limitation.

A severe strain (or grade III strain) is a complete rupture of the muscle which is usually accompanied by a “snap.” The injured person will not be able to continue activity or use the muscle at all.

A grade III strain usually is accompanied by significant pain when it happens and the individual is usually not able to continue participating in the activity. The site of injury may become swollen and a bruise may result from bleeding of the torn muscle. Once the swelling goes down, there will be an obvious gap in the muscle when one feels along the muscle.

The signs of a moderate strain are somewhere in between mild and severe. The person often feels a “pull.” There may be some pain, weakness, swelling, bruising, tenderness, and inability to continue the activity.