Strain is a muscle injury. The most common strains are strains of the muscles of the lower extremities, such as the strain of the thigh muscles, and the strain of the gastrocnemius (calf). There is no difference in gender and age.
Strains are divided into three categories:
First degree strains: small rupture of muscle elements.
Second degree strains: partial rupture of muscle elements, but maintenance of muscle continuity.
Third degree strains: complete cross section of the muscle, ie the muscle is cut.
Cause of a muscle strain
Muscles can be injured in two ways, by direct blows, or by over-stretching. The result is a rupture of muscle fibers (which can reach a full cross section of the muscle) and the formation of a hematoma.
The most common cause of a strain is a local injury to the muscle area, or to the myotendinous area near the joints. People who engage in sports activities are more likely to have strains. Also, people who have had strains in the past are more likely to have strains again in the same area.
There are several factors that contribute to muscle spasm:
- Poorly prepared muscles due to poor training or poor warm-up during exercise.
- Weak muscle due to previous injury and poor recovery.
- The muscle has developed scar tissue inelastic at the site of the previous strain.
- The muscle is overloaded and has reached a point of great fatigue.
- Tight muscles or muscles exposed to cold are more easily injured.
Preventing during sports activities and strengthening the areas that have a history of strains with elastic bandages, reduces the chances of muscle injury.
Obviously, the symptoms depend on the severity of the injury. In the case of muscle strain, the rupture of the muscle fibers is accompanied by the leakage of blood, which accumulates in the tissues causing hematoma, the dimensions of which are proportional to the severity of the injury. The main symptom is pain at rest, which is aggravated by the effort to move the muscle concerned and is accompanied by functional disability, making it impossible to use the affected muscle.
Muscle strains occur more in the area where the muscle connects to the tendon and less in the main muscle mass. The main symptoms in these conditions are immediate pain, local tenderness in the area, the development of edema (swelling), as well as the restriction of movement in the nearby joints. Ecchymosis (bruising) can often be seen immediately in the area of the strain. This is also called a hematoma.
Clinical examination is the main diagnostic tool in muscle strains. The use of ultrasound and magnetic resonance imaging in recent years complements the clinical examination and mainly helps to determine the size of the injury.
Complications after a muscle strain usually occur in cases of inadequate or incomplete treatment. They concern the increasing formation of scar tissue in the area of the strain, the creation of an encapsulated hematoma and the creation of bone tissue (ossifying myositis) which often leads to the limited functionality of the muscle and the joint in which it affects. Surgical treatment is usually the method of choice in these cases.
Treatment of a muscle strain
Conservative treatment is first and foremost the first approach to treating strains.
It consists of:
- Bandaging the muscle (upper or lower limb) with an elastic bandage
- Use of rest splints
- Administration of non-steroidal anti-inflammatory drugs
- Laying ice for the first two days
- Physiotherapy for rehabilitation, if necessary
- Second and third degree strains are assessed by the doctor and depending on other possible lesions, surgery (muscle suturing)
The physiotherapist with the means at his disposal, for the first 24 hours tries to reduce the swelling and pain using TECAR, TENS currents, cross currents and cryotherapy.
After the first 24 hours, the physiotherapist’s goal is to increase blood flow to the site of injury (via TECAR, ultrasound, hot pads, diathermy and laser) to achieve the maximum degree of nutrient supply for wound healing.
Then a program of stretching exercises is imposed on the injured muscle. After the rehabilitation, the isotonic exercises for additional strengthening gradually begin.
Following are specialized exercises of susceptibility and neuromuscular fitting, ie exercises of retraining the muscles for a safe return to daily activity.
Evans W.J., & Cannon J.G., (1991). The metabolic effects of exercise in muscle damage, Exercise Sport Sc. Rev, (19): 99 – 125.