Muscle strain is a soft tissue injury caused by indirect trauma, usually as a result
of muscle distention, or direct contusion, which can also lead to tears. The severity
of the injury depends on the affected fibres, and whether the muscle has completely
torn. Injuries can be classified as grade 1, 2, or 3, depending on the number of
damaged or ruptured fibres. They usually occur at the muscle-tendon junction
during maximum physical activity (sprinting, jumping, etc.), as a result of exceeding
the elasticity of the muscle belly. Some factors such as poor fitness, overloaded
muscles, lack of warm-up before exertion, muscle imbalance, age, etc., can
predispose to muscle strain with varying degrees of severity.
Sudden pain at the moment of the tear and immediate functional disability, with
pain remaining after injury, even at complete rest, and loss of the muscle’s
contractile function. Internal muscle bleeding with inflammation. The muscle is
well vascularised at the time of injury, causing haematomas.
Depending on the severity of the strain and the time elapsed, different rehabilitation
techniques can be applied to the injury, such as immediate cryotherapy, rest,
isometric therapy etc., always accompanied by compression garments or specific
orthoses that provide compression, support and heat to minimise fibre and
muscle-tendon tension during the healing period. This type of orthosis is highly
recommended as a method of prevention for patients returning to sporting activity.