Muscle tear is a type of sports injury or muscle injury that occurs when a muscle is overstretched or over-contracted beyond its limit. There are many movements and conditions that can cause a muscle tear as:
Muscle tears can range from mild to severe, depending on the quantity of the broken muscle:
Muscle tears can occur in any muscle, but they are most common in these muscles:
Muscle Tears can take several weeks or even months to heal completely.
The pathophysiology of the muscle tear can be divided into three phases:
The inflammation process starts in the immediate aftermath of the muscle tear, during which our immune system responds to promote healing and defend from infections. During this phase, the body releases chemicals (Histamine, Nitric Oxide ) that cause the blood vessels to dilate and become more permeable. This allows white blood cells and other immune cells to rush to the injured area to fight off infection and begin the process of repair.
The proliferation phase begins about 3-5 days after the injury. During this phase, the body begins to produce new tissue to repair the damaged muscle fibers.
These new fibers are formed by a process called myogenesis which is a complex process that involves the activation of satellite cells, which are dormant cells that are located within the muscle tissue. Satellite cells are responsible for the growth and repair of muscle tissue.
The proliferation phase can last for 2-3 weeks.
The remodeling phase begins about 2-3 weeks after the injury. During this process, the body begins to remodel the new muscle fibers making them stronger and more organized.
The new muscle fibers must be aligned and connected to each other. This process is called sarcomere alignment which is important for the strength and function of the muscle.
During the remodeling phase, the tissues are more organized as there is an alignment of the new muscle fibers in the same direction as the original muscle fibers.
The final step in the remodeling phase is the deposition of collagen. Collagen is a protein that is found in connective tissue. Collagen helps to strengthen the muscle and provide support banding the muscle fibers together.
The biomechanics of muscle fibers after a muscle tear is a complex process that involves the interaction of many different factors such as:
The severity of the muscle tear depends on the number of muscle fibers that have been damaged ( partial or total muscle tear ).
The location of the muscle tear is a fundamental aspect both for the symptoms and functionality of the torn muscle. A muscle tear in the middle of a muscle is more dangerous than a tear near the end of a muscle. This is because the two ends of a tear in the middle of a muscle are more likely to be pulled apart, which can lead to further injury. Additionally, tears in the middle of a muscle are more difficult to heal than tears near the end of a muscle.
The age and health of the individual reflect on the biomechanic quality of the muscle such as flexibility and strength.
In general, the biomechanics of muscle fibers after a muscle tear is characterized by the following:
First of all, it is important an early diagnosis of muscle tear, as very often mild muscle tears are missed as they cause minor pain or muscle dysfunction.
The diagnostic gold standard for a muscle tear is an Eco-Scan.
Experienced Physiotherapists or Sports Therapists can detect muscle tears with palpation of the muscles too. Under palpation, the muscle tear feels like a little depressed area that indicates the rupture of the muscle fibers.
If we assess a muscle tear with a clinical assessment instead of the diagnostic one ( Eco Sacn ), we have to be careful with the location of the bruised area of a torn muscle. Most of the time the bruised area is located a few centimeters down the location of the muscle tear because the blood went down the muscle because of gravity.
The photo below shows a Semitendinosus Muscle Tear with a bruised area located a few centimeters down the muscle.
The rehabilitation of a muscle tear is an important part of the healing process.
The goal of rehabilitation is to restore the strength, power, and range of motion of the affected muscle.
Rehabilitation typically involves a combination of different actions that include:
With proper rehabilitation, most people will be able to fully recover from a muscle tear and return to their previous level of activity. However, it is important to note that it may take several months for the muscle to fully heal.
It is important to note that it is not possible to completely eliminate the production of collagen tissue because it is part of the natural healing process.
However, we can reduce the amount of collagen tissue that is produced and improve the healing process.
There are a few things you can do to reduce the formation of scar tissue after a muscle tear, and these include:
Muscle tear is quite an important muscle injury.
If you may think or have a muscle tear, it is important to see a doctor or your trusted physiotherapist to get a diagnosis and discuss treatment options.
With proper care, most muscle tears will heal completely.
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