3D Medical Animation Depicting Strain-Tendon

A strain is an acute or chronic soft tissue injury that occurs to a

muscle Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of mus ...

tendon A tendon or sinew is a tough, high-tensile-strength band of dense fibrous connective tissue that connects muscle to bone. It is able to transmit the mechanical forces of muscle contraction to the skeletal system without sacrificing its ability ...

, or both. The equivalent injury to a

ligament A ligament is the fibrous connective tissue that connects bones to other bones. It is also known as ''articular ligament'', ''articular larua'', ''fibrous ligament'', or ''true ligament''. Other ligaments in the body include the: * Peritoneal l ...

is a

sprain A sprain, also known as a torn ligament, is an acute soft tissue injury of the ligaments within a joint, often caused by a sudden movement abruptly forcing the joint to exceed its functional range of motion. Ligaments are tough, inelastic fiber ...

. Generally, the muscle or tendon overstretches and partially tears, under more physical stress than it can withstand, often from a sudden increase in duration, intensity, or frequency of an activity. Strains most commonly occur in the foot, leg, or back. Immediate treatment typically includes five steps abbreviated as P.R.I.C.E.: protection, rest, ice, compression, elevation.

Signs and symptoms

Typical signs and

symptom Signs and symptoms are the observed or detectable signs, and experienced symptoms of an illness, injury, or condition. A sign for example may be a higher or lower temperature than normal, raised or lowered blood pressure or an abnormality showi ...

s of a strain include

pain Pain is a distressing feeling often caused by intense or damaging stimuli. The International Association for the Study of Pain defines pain as "an unpleasant sensory and emotional experience associated with, or resembling that associated with, ...

, functional loss of the involved structure,

muscle weakness Muscle weakness is a lack of muscle strength. Its causes are many and can be divided into conditions that have either true or perceived muscle weakness. True muscle weakness is a primary symptom of a variety of skeletal muscle diseases, includi ...

contusion A bruise, also known as a contusion, is a type of hematoma of tissue, the most common cause being capillaries damaged by trauma, causing localized bleeding that extravasates into the surrounding interstitial tissues. Most bruises occur clos ...

, and localized

inflammation Inflammation (from la, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants, and is a protective response involving immune cells, blood vessels, and molec ...

. A strain can range from mild overstretching to severe tears, depending on the extent of injury.

Cause

A strain can occur as a result of improper body mechanics with any activity (e.g.,

contact sport Contact sports are sports that emphasize or require physical contact between players. Some sports, such as mixed martial arts, are scored on impacting an opponent, while others, including rugby football, gridiron football and Australian rules f ...

s, lifting heavy objects) that can induce mechanical trauma or injury. Generally, the muscle or tendon overstretches and is placed under more physical stress than it can withstand. Strains commonly result in a partial or complete tear of a tendon or muscle, or they can be severe in the form of a complete tendon rupture. Strains most commonly occur in the

foot The foot ( : feet) is an anatomical structure found in many vertebrates. It is the terminal portion of a limb which bears weight and allows locomotion. In many animals with feet, the foot is a separate organ at the terminal part of the leg mad ...

, leg, or back. Acute strains are more closely associated with recent mechanical trauma or injury. Chronic strains typically result from repetitive movement of the muscles and tendons over a long period of time. Degrees of Injury (as classified by the American College of Sports Medicine): * First degree (mildest) – little tissue tearing; mild tenderness; pain with full range of motion. * Second degree – torn muscle or tendon tissues; painful, limited motion; possibly some swelling or depression at the spot of the injury. * Third degree (most severe) – limited or no movement; severe acute pain, though sometimes painless straight after the initial injury To establish a uniform definition amongst healthcare providers, in 2012 a Consensus Statement on suggested new terminology and classification of muscle injuries was published. The classifications suggested were: : The major difference suggested was the use of "indirect" muscle injury verse "grade 1" to provide subclassifications when advanced images were negative. Indirect Muscle Injury FUNCTIONAL (Negative MSK US & MRI) * Type 1: Overexertion-related Muscle Disorder ** Type 1a: Fatigue induced ** Type 1b: DOMS • Type 2: Neuromuscular muscle disorder ** Type 2a: Spine-Related ** Type 2b: Muscle-Related STRUCTURAL MUSCLE INJURY (Positive MSK US & MRI) • Type 3: Partial Muscle Tear • Type 4: (Sub) total tear DIRECT MUSCLE INJURY • Bump or Cut: Contact-related

Risk factors

Although strains are not restricted to athletes and can happen while doing everyday tasks, people who play sports are more at risk for developing a strain. It is common for an

injury An injury is any physiological damage to living tissue caused by immediate physical stress. An injury can occur intentionally or unintentionally and may be caused by blunt trauma, penetrating trauma, burning, toxic exposure, asphyxiation, o ...

to develop when there is a sudden increase in duration, intensity, or frequency of an activity.

Treatment

The first-line treatment for a muscular strain in the

acute phase Acute-phase proteins (APPs) are a class of proteins whose concentrations in blood plasma either increase (positive acute-phase proteins) or decrease (negative acute-phase proteins) in response to inflammation. This response is called the ''acute- ...

include five steps commonly known as P.R.I.C.E. * Protection: Apply soft padding to minimize impact with objects. * Rest: Rest is necessary to accelerate healing and reduce the potential for re-injury. * Ice: Apply ice to induce

vasoconstriction Vasoconstriction is the narrowing of the blood vessels resulting from contraction of the muscular wall of the vessels, in particular the large arteries and small arterioles. The process is the opposite of vasodilation, the widening of blood vess ...

, which will reduce blood flow to the site of injury. Never ice for more than 20 minutes at a time. * Compression: Wrap the strained area with a soft-wrapped bandage to reduce further

diapedesis Leukocyte extravasation (also commonly known as leukocyte adhesion cascade or diapedesis – the passage of cells through the intact vessel wall) is the movement of leukocytes out of the circulatory system and towards the site of tissue damage ...

and promote lymphatic drainage. * Elevation: Keep the strained area as close to the level of the heart as is possible in order to promote venous blood return to the systemic circulation. Immediate treatment is usually an adjunctive therapy of

NSAID Non-steroidal anti-inflammatory drugs (NSAID) are members of a therapeutic drug class which reduces pain, decreases inflammation, decreases fever, and prevents blood clots. Side effects depend on the specific drug, its dose and duration of ...

s and

Cold compression therapy Cold compression therapy, also known as hilotherapy, combines two of the principles of rest, ice, compression, elevation to reduce pain and swelling from a sports or activity injury to soft tissues and is recommended by orthopedic surgeons follow ...

. Cold compression therapy acts to reduce swelling and pain by reducing leukocyte extravasation into the injured area. NSAIDs such as

Ibuprofen/paracetamol Ibuprofen/paracetamol, sold under the brand name Combiflam among others, is a fixed-dose combination of the two medications, ibuprofen Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that is used for treating pain, fever, and inf ...

work to reduce the immediate inflammation by inhibiting Cox-1 and Cox-2 enzymes, which are the enzymes responsible for converting

arachidonic acid Arachidonic acid (AA, sometimes ARA) is a polyunsaturated omega-6 fatty acid 20:4(ω-6), or 20:4(5,8,11,14). It is structurally related to the saturated arachidic acid found in cupuaçu butter. Its name derives from the New Latin word ''ara ...

into

prostaglandin The prostaglandins (PG) are a group of physiologically active lipid compounds called eicosanoids having diverse hormone-like effects in animals. Prostaglandins have been found in almost every tissue in humans and other animals. They are deriv ...

. However, NSAIDs, including

aspirin Aspirin, also known as acetylsalicylic acid (ASA), is a nonsteroidal anti-inflammatory drug (NSAID) used to reduce pain, fever, and/or inflammation, and as an antithrombotic. Specific inflammatory conditions which aspirin is used to treat inc ...

and ibuprofen, affect platelet function (this is why they are known as "blood thinners") and should not be taken during the period when tissue is bleeding because they will tend to increase blood flow, inhibit clotting, and thereby increase bleeding and swelling. After the bleeding has stopped, NSAIDs can be used with some effectiveness to reduce inflammation and pain. A new treatment for acute strains is the use of

platelet rich plasma Platelet-rich plasma (PRP), also known as autologous conditioned plasma, is a concentrate of platelet-rich plasma protein derived from whole blood, centrifuged to remove red blood cells. Though promoted to treat an array of medical problems, ev ...

(PRP) injections which have been shown to accelerate recovery from non-surgical muscular injuries. It is recommended that the person injured should consult a medical provider if the injury is accompanied by severe pain, if the limb cannot be used, or if there is noticeable tenderness over an isolated spot. These can be signs of a broken or fractured bone, a

, or a complete muscle tear.Neustaedter, Randy
"Natural Treatment for Injuries"
Retrieved 5 December 2020.

References

External links