Muscle weakness, fatigue and pain all over the body, limbs? What are the causes?

Muscle weakness is a condition in which a person is unable to perform normal tasks with the upper or lower limbs. Muscles locally or globally throughout the body become prematurely tired and flabby.

In some cases, such weakness may be a sign of exhaustion after strenuous physical activity or sporting activity. However, unless there is an external cause or reason for such fatigue, muscle weakness is a symptom of one of a variety of diseases, not only of the musculoskeletal system.

Causes from nerves and muscles

Muscle weakness and increased muscle fatigue also occur as a result of problems of a nervous nature. Polyneuropathy is a disease of the peripheral nerves. There are several causes. Several types are known. They have different symptoms such as muscle weakness, tingling, impaired sensation, pain on touch, difficulty in walking, cramps, muscle twitching.

We know these types of polyneuropathy:

• Guillain-Barré syndrome
• Chronic inflammatory demyelinating polyneuropathy
• Multifocal motor neuropathy
• Alcoholic neuropathy
• Diabetic neuropathy
• Neuropathy in Lyme disease
• Monoclonal gammopathy
• Neuropathy in vasculitis
• Hereditary polyneuropathy

Neuromuscular disc involvement occurs, for example, in myasthenia gravis. Another example is congenital myasthenic syndrome, where muscle weakness is the main symptom.

Amyotrophic lateral sclerosis is a neurodegenerative disease, with a progressive loss of brain and spinal motoneurons and central nervous system cells. Symptoms include muscle weakness, muscle twitching, speech and pronunciation disorders and later problems with breathing and swallowing.

In neuritis, for example, muscle weakness is the most typical symptom. It affects muscles that are innervated by inflamed nerves.

In peripheral diabetic neuropathy, which affects people with diabetes, muscle weakness in the lower limbs is most common. In this disease, nerves are affected not only in function but also in structure.

In myopathy, where muscle weakness is also a typical symptom, the structure of the skeletal muscles is affected. The disease has several forms, such as muscular dystrophy, myostitis and other muscle tension disorders.

Becker's muscular dystrophy is another muscle disease. It is classified under genetic diseases. Its main symptoms are general physical weakness, muscle weakness. A person with this disease is physically weak, has difficulty walking fast, walking up stairs. After about 40 to 50 years of age, he is unable to walk. He has flaccid facial muscles, breathing difficulties, heart problems.

Another example is rhabdomyolysis, where there is damage to muscle cells. Rhabdomyolysis can be congenital but also acquired. Causes include muscle pain and weakness, elevation of muscle enzymes, and myoglobinuria (muscle cells in the urine).

Other diseases include:

• Glycogenosis
• Myotonic dystrophy
• Duchenne muscular dystrophy
• Brachial plexus muscular dystrophy - LGMD Limb - Girdle muscular dystrophy
• Myotonic Muscular Dystrophy - Girdle Girdle Muscular Dystrophy
• Distal dystrophy
• Dermatomyositis
• Polymyositis

Another case of muscle weakness is epilepsy. In the case of epilepsy, muscle weakness is caused by frequent epileptic seizures, which typically result in muscle spasms and twitching, which fatigues the muscles excessively.

A direct muscle disease is tennis elbow, in which there is acute or chronic overuse of the muscle and tendon tendons of the elbow joint.

Cardiovascular system

Excessive fatigue as well as muscle weakness can be a symptom of infective endocarditis. This is an acute disease of the inner lining of the heart that can even be life-threatening.

In myocarditis, for example, the heart musculature becomes inflamed as a result of infection. The body is affected by general weakness, increased fatigue and pain in the muscles and joints.

Similarly, with low blood pressure, which is due to a disorder of the blood vessels or the heart, for example, there is anaemia in some parts of the body, weakness and fatigue.

But problems can also affect people who have not only blood or blood vessel diseases, but also congenital or other heart defects. Also very dangerous is a congenital developmental defect of the heart and large vessels, coarctation of the aorta. In this case, cold feet and weakness of their muscles are manifested.

Various diseases of the blood and vascular system are also manifested by weakness of the muscles and the body. For example, in anemia, muscle weakness may occur from insufficient blood supply and oxygenation of specific muscles.

Digestive system

Several diseases of the digestive system can also be accompanied by muscle weakness and problems with general weakness and fatigue of the body. For example, in celiac disease, this is due to impaired absorption of nutrients important to the body.

Muscle weakness also occurs in chronic inflammation of the small or large intestine, which is typical of Crohn's disease. In pancreatic cancer, the body is generally weakened, there is muscle fatigue and also weight loss.

However, cancers and tumours can also affect other parts of the digestive system. For example, a common complication of colon cancer is a lack of iron in the blood, which results in anaemia accompanied by fatigue and weakness. Stomach cancer is also associated with fatigue, weakness and weight loss.

Increased muscle fatigue and weakness, as well as general malaise, are also typical of liver diseases such as haemochromatosis. However, other liver diseases such as infectious hepatitis or liver failure may also be involved.

Lower limbs and disorders

There is also a problem with ischaemic disease of the lower limbs. A blockage forms in the artery that supplies blood to the lower limbs. The lower limbs lose their strength, especially in the muscles.

Weakening of the muscles is sometimes part of varicose veins, especially when they affect the lower limbs, which can be painful and also swollen.

Infectious diseases

In some infectious diseases, muscle weakness can be present chronically, such as in AIDS. This weakens a person's immune system.

Lyme disease is also an infectious disease, affecting, for example, the skin, the nervous system, the joints and the heart. It is also characterised by fatigue, headaches, muscle pain and weakness.

Even with the parasitic infection toxoplasmosis, muscle problems, pain, cramps and weakness can be observed. Shingles, a disease with typical pimples, is also characterised by general weakness, malaise and muscle weakness.

Weakness also occurs with brucellosis, which is primarily a disease of animals, but in some cases is transmitted to humans, especially to people who work near infected animals.

There are four known species that are transmitted to humans: Brucella abortus (cattle), Brucella suis (pigs), Brucella melitensis (goats and sheep) and Brucella canis (dogs). Depending on the causative agent, they cause symptoms, including muscle weakness, muscle pain, fever, shivering, sweating, fatigue and lack of appetite.

Other causes

Similar is the case with acute myeloid leukemia, which is one form of blood cancer. There is fatigue, weakness and increased temperature in affected people. In multiple myeloma, which is a cancer in the bone marrow, muscle weakness is also present.

Physical and muscular weakness is also typical of congenital diabetes, which arises from insufficient insulin production in the pancreas. It can also stem from disturbances in hormones and their levels. For example, in pituitary adenoma, the proper functioning and production of hormones is disturbed.

There is muscle weakness acromegaly, i.e. enlargement of certain parts of the body. With reduced production of thyroid hormones (hypothyroidism), people affected by this disease complain not only of muscle weakness, but also of general weakness of the organism.

Pellagra is a vitamin B3 (niacin) deficiency disease. Muscle weakness is also one of the symptoms. Weakness also occurs in eating disorders such as anorexia or malnutrition.

Of course, muscle weakness also occurs as a symptom of various musculoskeletal disorders. Sometimes it is caused by injury, but it can also be due to various disease conditions.

For example, in carpal tunnel syndrome, the hand is weakened as a result of oppression of the nerves in the wrist. This happens when there is a permanent compression of these nerves.

It is a rule that muscle weakness also occurs with fever, which can be a symptom of an illness, such as the flu. And even the flu itself, before the onset of fever, manifests itself in fatigue and muscle weakness.