The 3 Grades of Muscle Strains and Symptoms of a Muscle Tear

Your doctor may use X-rays or MRI scans to test for a muscle tear.
Image Credit: Pornpak Khunatorn/iStock/GettyImages

A muscle tear falls under the umbrella of muscle strain, defined by Harvard Health Publishing as a "stretching or tearing of muscle fibers." Muscle strains may occur because the muscle has been stretched too far or because it has contracted with too much force.


The risk of a muscle tear is highest for those involved in contact sports such as football, although you can also tear a muscle doing heavy lifting or other non-sports-related activities.

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Whatever the cause, if you suspect you've torn a muscle, you may want to pay a visit to your doctor. There are a few ways your doctor can test for a muscle tear such as observing and asking about symptoms or using X-rays or MRI scans.


Grades of Muscle Strains

Muscle strains can be classified into three different grades depending on the severity of the fiber damage:

  • Grade I Strain

    The injured muscle may be sore, but it has its normal strength. In this case, only a few muscle fibers are torn or stretched.


  • Grade II Strain

    With this strain, you may experience mild swelling and bruising as well as more severe muscle pain and tenderness due to a larger number of injured fibers.

  • Grade III Strain

    This strain can cause complete loss of muscle function along with severe pain and swelling. The strain tears the muscle all the way through, either ripping it into two separate pieces or shearing it away from its tendon.


Muscle Tear Symptoms

There are a number of ways to identify a muscle tear. Symptoms include:

  • Muscle cramps or spasms
  • Depletion of muscle strength or complete loss of function
  • A pop in the muscle at the moment of injury
  • A dent, gap or other abnormality of the muscle
  • Muscle swelling and/or discoloration
  • Pain or tenderness in the muscle after an activity that stretches or contracts the muscle (pain increases when you move the muscle and decreases when you're in a resting position)


Read more: What Are the Treatments for a Torn Muscle?

Ways to Test for a Muscle Tear

First, consult your doctor if you're experiencing muscle strain symptoms. Let her know what triggered the muscle strain and whether there was a pop at the time of injury.


In addition, let your doctor know if you've experienced other symptoms, such as fever, weight loss, numbness or urinary/bladder problems. She will then go on to evaluate whether you have a muscle tear by:


  • Examining you to check for spasms, muscle weakness or tenderness and decreased muscle movement. If this exam indicates mild or moderate strain, you may not need further testing.
  • Taking a muscle X-ray, which can show if the tendon has pulled off a piece of bone where it attaches. Note that pure muscle injuries can't be seen on X-rays.
  • Performing an MRI scan to determine whether the tear is partial or complete and its specific location. MRIs can also show the presence of a hematoma, a collection of blood that can occur following severe injuries.

Read more: Supplements to Repair a Torn Muscle




Is this an emergency? If you are experiencing serious medical symptoms, please see the National Library of Medicine’s list of signs you need emergency medical attention or call 911.

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