Strain (injury)
An acute muscle injury from tearing of fibers.
A strain is an acute soft tissue injury that occurs to a muscle, involving tearing of some muscle fibers. The equivalent injury to a ligament is a sprain. Strains are usually the result of an eccentric contraction, meaning the muscle is lengthened while it is contracting. The body repairs strains, and treatments can alleviate symptoms.
- type
- Muscle injury
- common_symptoms
- Pain, interference with activities, difficulty generating strength due to pain
- common_signs
- Tenderness, pain with stretch of the muscle
- common_causes
- Improper body mechanics, overstretching, mechanical trauma
- classification_system
- American College of Sports Medicine degrees (first, second, third); 2012 Consensus Statement (indirect/direct muscle injury)
- first_line_treatment
- P.R.I.C.E. (Protection, Rest, Ice, Compression, Elevation)
Lore & Background
A strain occurs when a muscle or tendon overstretches and is placed under more physical stress than it can withstand, commonly resulting from improper body mechanics during activities such as contact sports or lifting heavy objects. Strains most commonly occur in the foot, leg, or back. Acute strains are associated with recent mechanical trauma, while chronic strains result from repetitive movement over a long period. The injury can range from mild overstretching to severe tears, including complete tendon rupture.
Reader's Guide
The classification of strains has evolved to establish uniform definitions among healthcare providers. The American College of Sports Medicine defines three degrees: first degree (little tissue tearing, mild tenderness), second degree (torn tissue, painful limited motion), and third degree (limited or no movement, severe acute pain). In 2012, a Consensus Statement suggested new terminology, distinguishing indirect muscle injury (functional or structural) from direct muscle injury (bump or cut). Treatment focuses on the acute phase with P.R.I.C.E. (Protection, Rest, Ice, Compression, Elevation) and adjunctive therapies like NSAIDs and cold compression. Platelet rich plasma (PRP) injections have shown to accelerate recovery from non-surgical muscular injuries. Medical consultation is recommended for severe pain, inability to use the limb, or noticeable tenderness over an isolated spot, as these may indicate fracture, sprain, or complete muscle tear.
Did You Know?
- A strain is an acute soft tissue injury to a muscle, while the equivalent injury to a ligament is a sprain.
- Strains are usually the result of an eccentric contraction, where the muscle lengthens while contracting.
- The American College of Sports Medicine classifies strains into three degrees, from mildest (first) to most severe (third).
- A 2012 Consensus Statement suggested new terminology for muscle injuries, including 'indirect muscle injury' and 'direct muscle injury'.
Frequently Asked Questions
What is Strain (injury) in the Musculoskeletal System And Orthopedics canon?
A strain is an acute soft-tissue injury in which some of the muscle's fibers are torn. It is the muscle-specific counterpart to a sprain, which affects ligaments rather than muscle tissue.
What typically causes a Strain (injury) to occur?
Strains most often result from an eccentric contraction, where the muscle is being stretched while simultaneously trying to contract. Other common triggers include poor body mechanics, overstretching, and direct mechanical trauma.
What symptoms and signs does a Strain (injury) produce?
Affected individuals typically report pain, reduced ability to perform daily activities, and an inability to generate normal strength because of that pain. On examination, clinicians look for localized tenderness and pain reproduced when the involved muscle is passively stretched.
How is a Strain (injury) classified in the canon?
The American College of Sports Medicine grades strains into first-, second-, and third-degree categories based on severity. A 2012 Consensus Statement also distinguishes between indirect and direct muscle injuries, adding another layer to the classification framework.
What is the standard first-line treatment for a Strain (injury)?
The P.R.I.C.E. protocol—Protection, Rest, Ice, Compression, and Elevation—is the go-to initial management strategy. The body's own healing mechanisms repair the torn fibers, and these interventions help reduce swelling and ease symptoms during recovery.
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