Four Types of Skeletal Muscle Injuries You Should Know About

Written by Sarah Thebarge, Physician Assistant

There are over 600 muscles in your body! These muscles are categorized into three main types: cardiac, smooth, and skeletal:

• Cardiac muscle tissue forms the walls of your heart.
• Smooth muscle tissue is found in the walls of hollow organs like the bladder, as well as in passageways like the airway and gastrointestinal (GI) tract.
• Skeletal muscle is the most common muscle tissue in the body and is prone to injury. Skeletal muscles attach to bones via tendons to facilitate your body’s movement and strength. Here are four types of skeletal muscle injuries you should know about:

Muscle Strain

A muscle strain is commonly referred to as a “pulled” muscle. This injury can happen when the muscle is overstretched, overused, or used improperly. Muscle strains result in microscopic tears in the muscle fibers. Common sites for strain injuries include the hamstring, shoulder, neck, and lower back.

Strains can result in muscle soreness, stiffness, weakness, swelling, and spasms. They usually heal over the course of a few weeks. Interventions like ice, anti-inflammatory medications, and gentle stretching can often help the injury heal faster.

Muscle Tear

While a muscle strain refers to a microscopic injury to muscle fibers, a muscle tear is a larger injury in which a muscle and the blood vessels that supply it are torn. It typically takes a significant amount of force to cause this type of injury. Like a muscle strain, the most common muscle tears occur in the lower back, neck, shoulder, and hamstring.

Muscle tears often cause a sudden onset of severe pain, as well as bruising, swelling, and weakness. Anyone who sustains this type of injury should seek urgent medical attention. Patients who have a torn muscle also often require follow-up care and rehabilitation with physical therapy.

Rhabdomyolysis

Rhabdomyolysis is a serious condition that occurs when muscle fibers die and their contents are released into the bloodstream. Since the kidneys filter out these muscle byproducts, rhabdomyolysis can result in kidney failure, which may be fatal in some cases.

Symptoms of rhabdomyolysis include muscle pain, weakness, and dark urine.

Causes of rhabdomyolysis maybe traumatic or non-traumatic. Examples of traumatic rhabdomyolysis include crush injuries, car accidents, or lying unconscious on a hard surface for a long period of time. Non-traumatic muscle injury can be caused by heatstroke, infections, intense exercise, seizures, and the use of certain recreational drugs like cocaine and amphetamines.

Muscle Contusion

A muscle contusion is commonly referred to as a muscle “bruise.” This type of injury occurs when a blunt object strikes the body and crushes underlying muscle tissue, but does not break the skin. Contusions typically cause pain, swelling, and decreased range of motion. They also often cause visible bruising because blood from damaged blood vessels pools underneath the surface of the skin.

While mild contusion injuries often heal with ice, rest, and time, more serious injuries sometimes require surgical intervention to address excessive pressure that can accumulate from internal swelling and bleeding.

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