Breaking Point: The Physiology of Muscle Strains and Tears

How do Muscle Strains/Tears Occur?

Structurally, muscles are made up of thousands of small fibers that are woven together. When these fiber strands are stretched beyond their limit, they tear apart resulting in a strain or tear of the muscle. A muscle strain is an overstretching or minor tearing of muscle fibers, while a muscle tear is a more severe injury involving partial or complete rupture of the muscle or tendon. A muscle tear occurs when the force applied to that muscle outweighs its structural capacity causing damage to its fibers.

Generally, muscle strains are classified as either acute or chronic, with acute strains often occurring suddenly with immediate symptoms while a chronic strain may develop gradually over time (Cleveland Clinic, 2022). Muscle tears are more severe and can be the result of overuse, overstretching, sudden movements, trauma, poor conditioning, etc. Overuse and overstretching of muscles can lead to injury where repetitive strain or pulling a muscle past its normal range can wear down the body or cause fibers to break apart. Sudden and forceful movements, such as sprinting, jumping, or rapid changes in direction can lead to minor or complete tears in the muscle. Trauma can force muscles beyond their limits, while fatigue can cause weakened muscles to be more prone to injury.

Most Common Types of Muscle Strains and Tears:

Some of the most common types of muscle strains and tears involve the:

• Abdominal muscles

• Back muscles

• Groin muscles

• Hip flexor muscles

• Calf muscles

• Hamstring muscles

While all of the reasons listed above are potential reasons for muscle injuries, there are some factors that tend to affect particular groups over others. For example, back muscles are generally injured as a result of overuse as a result of physically demanding jobs. Calf and hamstring muscles are often common sports related injuries and can be injured as a result of sudden, extreme movements. Abdominal muscles often are injured during exercise due to improper technique causing overstretching or excessive strain. Regardless of how a muscle may become strained or torn, it is important to understand how to appropriately take care and rehabilitate the injured muscle.

Muscle Strain Grading and how to Treat Injuries:

Muscle strains are graded on a scale of 1 to 3, with 1 being the least severe and 3 being a complete tear of the muscle. A grade 1 muscle strain results in only a few muscle fibers being torn, with pain generally being localized to that area. Those affected with a grade 1 strain generally have no loss of movement or strength along with little to no swelling. A grade 2 strain is a partial muscle tear that results from a larger number of muscle fibers being torn. Individuals will generally feel a sharp and sudden pain at the time of the injury with swelling likely to occur. A grade 3 strain is a complete rupture of the muscle that will involve all or nearly all of the muscle fibers torn apart. This will result in severe pain and swelling of the area, and most often will require medical attention through surgical intervention or intense rehabilitation efforts (Walden, 2019).

Diagnosis of a grade 1 to 3 muscle strain generally involve a medical examination and sometimes require imaging tests like an MRI or ultrasound to assess the exact severity of the injury. Unless surgery is required, treatment is largely the same and involves the RICE method of Rest, Ice, Compression, and Elevation (Walden, 2019). Over the counter pain medications can help mitigate minor pain while prescription medications will likely be needed for more severe injuries. Depending on the muscle and grade of injury, it can take weeks to months to fully heal a muscle strain, with return to activity limited to prevent re-injury. To help prevent muscle injuries from occurring in the first place or from re-occurring, it is important to stay hydrated and stretch often, promoting improved muscle flexibility.

Sources:

Cleveland Clinic. (2022, January 28). Muscle Strains: Causes, Symptoms, Treatment & FAQs. Cleveland Clinic. https://my.clevelandclinic.org/health/diseases/22336-muscle-strains

Walden, M. (2019, September 8). Muscle Strain - Grade 1, 2 & 3 Torn Muscles Explained. Sportsinjuryclinic.net. https://www.sportsinjuryclinic.net/sport-injuries/muscle-strains

Assessed and Endorsed by the MedReport Medical Review Board