There are numerous diseases of the muscular system. According to the U.S. National Library of Medicine and the National Institutes of Health, muscle disorders can cause weakness, pain or paralysis, and some of the most common causes of muscle disorders include: overuse injuries, genetics, certain cancers, inflammation, nerve-related diseases, infections and some medications. Muscular system diseases can range from mild to severe, and can affect a person's daily activities.
Fibromyalgia
Fibromyalgia is a disease of the muscular system. According to the Mayo Clinic website, fibromyalgia is a chronic condition that involves diffuse muscle, ligament and tendon pain, along with fatigue and numerous tender points. Even slight pressure applied to the tender points can cause a person severe pain. MayoClinic.com states that fibromyalgia occurs in approximately 2 percent of Americans, that women are more susceptible to the disease than men and that the likelihood of a person developing fibromyalgia increases with age. Fibromyalgia symptoms may arise after a traumatic physical or emotional event, although in many instances there is no single precipitating factor. Common fibromyalgia symptoms include: total body pain, tender points throughout the body and feeling tired after seemingly plenty of sleep. MayoClinic.com states that fibromyalgia is often accompanied by other conditions, such as depression, headaches and osteoarthritis, among others.
Polymyalgia Rheumatica
Polymyalgia rheumatica is a disease of the muscular system. The American College of Rheumatology states that polymyalgia rheumatica is a relatively common cause of diffuse aching and stiffness in adults 50 and older, and that it may be accompanied by giant cell arteritis--an inflammatory disease of the blood vessels. Polymyalgia rheumatica can be difficult to diagnose, as it typically does not cause joint swelling or other easily identifiable signs during a physical examination. The ACR notes that the most common symptoms of polymyalgia rheumatica include pain and stiffness in the upper arms, neck, lower back and thighs, and that symptoms often develop quickly, sometimes even overnight. A person with polymyalgia rheumatica will experience symptoms on both sides of her body, and may have trouble raising her arms above her shoulders.
McArdle's Disease
According to McArdlesDisease.org, McArdle's disease is a rare, inherited muscle disease--a glycogen storage disease, specifically--that affects about one in 100,000 people, and that it is an autosomal recessive genetic disorder in which a person is unable to break glycogen down into glucose. Because a person with McArdle's disease lacks the enzyme glycogen phosphorylase--the enzyme responsible for glycogen breakdown--he may feel fatigue during physical exertion or exercise. McArdlesDisease.org states that McArdle's disease can cause painful cramping injuries that require medical intervention, and that although McArdle's disease can limit physical activity, it's not necessarily a life-threatening condition, as long as the proper precautions are taken. With appropriate lifestyle management, notes McArdlesDisease.org, a person with McArdle's disease can live a healthy, active life.
