Pain in the muscles (myalgic syndrome)

The pain in the muscles can be spontaneous, occur during physical exertion, either retarded or at rest. Sometimes the pain is detected only when palpation.

During physical exertion, ischemic pain develops (for example, intermittent claudication or angina pectoris); retarded pain is more typical for structural changes in muscles (inflammatory changes in connective tissue). At the same time, patients can complain about stiffness, spasms and cramps. Pain is usually described by patients as blunt. Acute lancinating pains are rare (for example, with myofascial syndrome). As a rule, pain increases with an arbitrary reduction.

Crumpies are also accompanied by severe pain. Contracture is an extremely rare form of involuntary contraction and is caused by a decrease in muscle adenosine triphosphate; it is characterized by electrical silence in the muscles. Sometimes spasm of muscles develops as a reflex reaction of muscles around the damaged tissues. Carpopedal spasms in tetany are often painful. Less commonly, the cause of muscle pain is myotonia or dystonia.

Suffice it to identify the swelling of the diseased muscles, which always indicates a serious disease (polymyositis, dermatomyositis, myophosphorylase deficiency and phosphofructokinase, acute alcoholic myopathy). The pain in the muscles is sometimes paroxysmal and can disturb the night's sleep.

[1], [2], [3], [4], [5], [6]

Causes of muscle pain

Diffuse (generalized) pain in the muscles

1. Fibromyalgia
2. Rheumatic polymyalgia
3. Myalgia in common infectious diseases.
4. Poliomyositis, dermatomyositis.
5. Syndrome of painful fasciculations and cramps.
6. Metabolic myopathies
7. Myoglobinemia
8. Eosinophilia-myalgia syndrome.
9. Guillain-Barre syndrome
10. Electrolyte disorders (hypokalemia, hypocalcemia, hypernatremia)
11. Endocrine myopathies (hypothyroidism, hypoparathyroidism, hyperparathyroidism)
12. Iatrogenic
13. Psychogenic myalgia
14. Parasitic myositis

Local (localized) pain in the muscles

1. Arterial insufficiency (ischemia of the calf muscles)
2. Myalgia in chronic venous insufficiency
3. Myofascial pain syndrome
4. Temporal arteritis

[7], [8], [9]

Diffusive (generalized) muscle pains

Fibromyalgia is defined as non-rheumatic extraarticular non-inflammatory chronic diffuse muscular pain with a kind of tension (stiffness), and fatigue (fatigue) of the muscles. Patients with fibromyalgia account for up to 5% of all patients in general practice. At the same time, 80-90% of them are women aged 25 to 45 years. Fibromyalgia is characterized by: spontaneous diffuse (bilateral and symmetrical) pain; the presence of painful points (11 of 18 described tender points are required for the diagnosis, and the duration of the disease should be at least 3 months); characteristic syndromic environment of the pain syndrome in the form of vegetative, mental and somatic disorders (depression, asthenia, sleep disorders, tension headaches or migraines, frequent occurrences of the Reynaud phenomenon, hyperventilation disorders, panic attacks, cardialgia, syncopal conditions).

Rheumatic polymyalgia is a disease affecting patients aged 55 years and showing the stiffness of proximally located muscles, especially in the shoulder region. Often revealed mild anemia, weight loss and general malaise. Typically, an increase in ESR above 50 mm. Unlike polymyositis, rheumatic polymyalgia is accompanied by normal indices of creatine kinase, muscle biopsy, and EMG. Corticosteroids (40 - 60 mg per day) usually give dramatic therapeutic effect.

Myalgia (pain in the muscles) in common infectious diseases (influenza, parainfluenza and other infections) is a common and well-known phenomenon. Myalgia is characteristic of the acute stage of infection. They are quite typical for brucellosis. Primary infectious myositis (viral, bacterial and parasitic) are rare. An epidemic myalgia (Bornholm disease) is described; the disease occurs in the form of outbreaks, more often in children's groups, or sporadically. Pain in the muscles is accompanied by fever, headache, sometimes vomiting, diarrhea. The pains are localized mainly in the muscles of the abdomen and chest, proceed in the form of strong paroxysms.

Poliomyositis and dermatomyositis. With polymyositis, muscle pain and muscle weakness are often the leading complaints. The disease is more common among women and is manifested by acute or subacute development of weakness of proximally located muscles (myopathic syndrome), early appearance of dysphagia, muscle tension (painful tightening), the preservation of tendon reflexes and skin involvement (dermatomyositis). Often other systems are involved (lung, heart, in 20% of cases, dermatomyositis accompanies carcinoma). In men, poliomyositis is more often paraneoplastic in nature, in women it is autoimmune. The diagnosis is confirmed by muscle biopsy, electromyography, increased ESR (in 60% of cases) and creatine phosphokinase (in 70%).

The syndrome of "painful facies and cramps" (benign fasciculation syndrome, syndrome of cramp-fasciculations) is manifested only by these symptoms in the absence of signs of denervation on EMG; the rate of excitation is also normal.

Metabolic myapathies associated with impaired energy metabolism include disorders of glycogen metabolism (glycogenases V, VII, VIII, IX, X and XI types); mitochondrial myopathies (carnitine-palmitoyltransferase insufficiency

The deficiency of myophosphorylase (Mc-Ardl's disease, type V glycogenosis) usually begins to appear at a young age with painful muscle tension (stiffness), cramps, contractures and muscle weakness, which are induced by intense physical exertion. Symptoms disappear after a period of rest, but can persist for several hours. Over the years, the manifestations of the disease become less pronounced. An elevated level of creatine phosphokinase is noted. EMG can be normal or detect myopathy; biopsy shows excess deposits of glycogen with reduction or absence of myophosphorylase.

Lack of phosphofructokinase or disease Tarui, glycogenesis of type VII, shows symptoms similar to Mac-Ardl's disease, but begins in early childhood and is less often accompanied by contractures. The diagnosis is confirmed by the lack of phosphofructokinase and the accumulation of glycogen in the muscles. Creatine phosphokinase increases between attacks of muscle pain. A similar picture is described with other types of glycogenoses.

Insufficiency of carnitine-palmitoyltransferase appears from an early, sometimes neonatal age, from episodes of nausea, vomiting, non-ketone hypoglycemic coma. Episodes of coma are provoked by starvation, intercurrent infection, and in more mature age - and physical activity. Young adults with muscle carnitine deficiency have proximal muscle weakness and muscle pain.

Possible attacks of muscle pain, weakness and myoglobulinuria, provoked by prolonged physical exertion, especially after fatty foods. A muscle biopsy shows the accumulation of lipids. The level of CK is usually elevated.

Other types of mitochondrial myopathies also manifest themselves in muscle weakness, myalgia, which is provoked by physical exertion. The pathology of the mitochondria is usually detected by electron microscopy.

Myoglobinemia. Myoglobin is a protein that plays an important role in storing oxygen and transporting it to the skeletal muscle. Myoglobinemia is an early indicator of muscle damage. Myoglobinemia syndromes (with mechanical trauma such as crash syndrome, poisoning with myolytic poisons that lead to toxic myositis, violations of arterial or venous circulation in the extremities, burns, frostbites, convulsions in tetanus, epilepsy, generalized torsion dystonia, malignant neuroleptic syndrome) are accompanied, in addition to other symptoms, muscle pain and myoglobinuria.

Eosinophilia-myalgia syndrome was described as an epidemic outbreak among people taking L-tryptophan. It was manifested by myalgic syndrome, fatigue, eosinophilia, pneumonia, edema, fasciitis, alopecia, skin manifestations, myopathy, arthralgia and neuropathy. Expressed krumpi and spasms were observed in the axial muscles as a late complication. Postural tremor and myochemia, as well as myoclonus, are described as unusual delayed manifestations. Over time, the condition improves, although chronic myalgia and fatigue, as well as some somatic manifestations can persist for a long time.

Myalgias are sometimes observed in Guillain-Barre syndrome as a symptom that precedes the development of flaccid paresis, the appearance of which reveals the cause of myalgia.

Electrolyte disorders (hypokalemia, hypocalcaemia, hypernatremia) when using diuretics or laxatives; with hyperaldosteronism or metabolic acidosis, malnutrition and malabsorption may be accompanied by myalgia and krampi. The study of electrolyte balance here acquires an important diagnostic value.

Endocrine myopathies (pain in the muscles) (associated with hypothyroidism, hyperthyroidism, hypoparathyroidism and hyperparathyroidism). Hypothyroid myopathies differ in infants, children and adults. In infants and children, hypothyroidism often leads to generalized muscle tension (stiffness), and hypertrophy, especially noticeable in the calf muscles, which is known as the Kocher-Debre-Semelaigne syndrome. Adults with hypothyroid myopathy show a moderate weakness of the muscles of the shoulder and pelvic girdle; three-fourths of these patients complain of muscle pain, cramp or muscle tension. Muscular hypertrophies sometimes accompany this syndrome (Hoffman's syndrome - Hoffman). Rarely rhabdomyolysis is rare. Typically, the slowing down of both muscle contraction and relaxation (especially in the cold). It is possible to increase the level of creatine phosphokinase.

Muscle pain and cramps are often observed with hypoparathyroidism and hyperparathyroidism. In the latter case, the exact mechanism of these symptoms is not known.

Iatrogenic pain in muscles (and krampi) can be observed after gastrectomy, dehydration and administration of such drugs as gamma-aminocaproic acid, vincristine, lithium, salbutamol, emetine, amphetamine, alcohol, nifidipine, nicotinic acid, cyclosporine, levodopa, penicillin. The identification of the relationship between myalgia and the administration of the drug confirms the diagnosis.

Psychogenic pain in muscles is typical for conversion disorders and are observed in the picture of other psychogenic syndromes (motor, sensitive, vegetative). Another pattern of chronic pain syndrome is typical of depression ("pain-depression" syndrome), which can be either explicit or hidden. Identification of emotional-affective and personality disorders and exclusion of organic causes of myalgia is crucial for diagnosis and therapy of these disorders. There may be pain in the muscles and with psychosis.

Myalgia (pain in the muscles) is a typical symptom of parasitic myositis (trichinosis, cysticercosis, toxoplasmosis); are now rare.

[10], [11], [12]

Local (localized) pain in the muscles

Arterial insufficiency of the lower extremity (claudicatio intermittens) has characteristic clinical manifestations in the form of periodic pains in the gastrocnemius muscle that arise during walking and disappearing after a stop, is confirmed by ultrasound examination of the main arteries on the leg.

Myalgias with chronic venous insufficiency are usually observed in the legs and are accompanied by other symptoms of phlebopathy (varicose veins, trophic disorders); it is necessary to exclude other possible causes of pain syndrome.

Myofascial pain syndrome is characterized by trigger points and characteristic reflex pains of one or another localization. For the diagnosis is important palpatory examination of the muscles and knowledge of the typical zones of reflected pain.

Temporal arteritis (systemic granulomatous vasculitis with predominant lesion of extra- and intracranial arteries) is accompanied by unilateral or bilateral constant or pulsating pain in the temporal region. A convoluted dense and painful temporal artery is revealed on the background of other neurological and somatic symptoms of this systemic disease that affects predominantly mature and elderly women (high ESR, fever, anemia, decreased vision, etc.). Biopsy reveals a picture of giant cell arteritis. Pain syndrome increases with palpation of the temporal artery and temporal muscles, but more often the myalgic syndrome has a more generalized character.

In healthy people, localized muscle pain often develops after excessive physical exertion on certain muscles. It is transient in nature and usually takes a few hours or days to complete.