Behind muscle complaints there can be numerous triggers, harmless and serious ones. The following overview offers only a selection of important causes. It is not exhaustive and should not be taken as a guide to self-diagnosis. The diagnosis can only be made by a doctor after a thorough examination.
Muscle pain often occurs after injury and overuse (for example, bruising, torn muscle fibers "muscle soreness"). There is usually a clear temporal connection with a triggering event. If this is not the case, various other reasons come into question. Circulatory disorders, mostly of the legs, can manifest themselves in typical walking-distance-dependent pain that recedes when the patient is standing (pAVK, Claudication intermittens). Polyneuropathies (nerve damage, often in the context of diabetes, but also due to chronic alcohol consumption or vitamin deficiencies, for example vitamin B deficiency) can also manifest as muscle pain. Typically, sensory disturbances such as tingling or numbness also occur here. Generalized muscle pain is also common in the context of viral infections (for example, flu or influenza). Certain rheumatic diseases (such as muscular rheumatism or fibromyalgia syndrome) can also cause severe muscle pain. Nocturnal muscle pain in the legs can also be caused by restless legs syndrome.
Muscle cramps can be caused by deficiencies of certain blood salts (such as potassium, sodium, or magnesium). A deficiency of these electrolytes sometimes occurs in the context of treatment with diuretics (water tablets) – or through fluid and salt losses via the gastrointestinal tract (for example, in the case of gastrointestinal infections, chronic use of certain laxatives) or through heavy sweating.
Muscle weakness regularly occurs under conditions of physical inactivity, for example due to prolonged bed rest due to illness or due to immobilization of individual extremities after an injury. Increasingly, attempts are being made to counteract this development through early functional treatment methods. Various general diseases can also affect the muscles (secondary myopathies). These include hypothyroidism, Cushing's syndrome (hypercortisolism, which means too much cortisol in the blood), advanced kidney dysfunction or phosphate deficiency. In some cases, neurological diseases are the cause of muscle weakness. This includes disorders of the nerves (such as spinal cord injuries or diseases with paraplegic symptoms, multiple sclerosis, Guillain-Barre syndrome, polio, amyotrophic lateral sclerosis) or muscle diseases (for example, myasthenia gravis, muscular dystrophy). In addition to flaccid muscle paralysis, there is also paralysis of the muscles due to increased muscle tension (spastic paralysis). Spastic paralysis is typical of damage to certain regions of the brain (for example, due to oxygen deprivation of the newborn during birth or due to stroke, multiple sclerosis) and spinal cord (as in paraplegia). This article contains only general information. Must not be used for self-diagnosis or self-treatment. It cannot replace a visit to the doctor.