The muscular system consists of tissues that control and assist in movement of every part of the body. It interacts with the nervous system to maintain postural support and generate heat. According to Medical-look.com, there are over 600 muscles in the body, accounting for about 40 percent of the body weight of average-sized individuals. Muscle diseases vary according to the muscle type.
Muscular Dystrophy
Muscular dystrophy, a disorder that causes the muscles to break down and weaken, is a broad term covering many specific types. Duchenne's muscular dystrophy affects the skeletal muscle system. Facioscapulohumeral muscular dystophy or FSHD (Landouzy-Dejerine syndrome) affects the muscles in the face, shoulder and arm, according to health-cares.net.
Myasthenia Gravis
Muscle weakness that progresses throughout the day is a typical symptom of myasthenia gravis. According to the National Institute of Neurological Disorders and Stroke, normal impulses to the nerve are blocked. Initial signs may include difficulty swallowing or weakness in the eye muscles. The body is being attacked by its own immune system.
Compartment Syndrome
Compartment syndrome is most often related to the lower legs. This painful condition is a result of dangerous pressure levels within the muscles. Chronic compartment syndrome is a disease process most often related to some type of physical or athletic activity. Acute compartment syndrome is most likely the result of an injury. Symptoms can include an aching, burning pain; limb tightness; and numbness or weakness in the affected muscle.
Soft Tissue Sarcoma
Soft tissue sarcoma is a type of cancer that develops in muscles, tendons, fat, nerves and synovial tissues. According to the National Cancer Institute, soft tissue sarcomas include the diseases leiomyosarcoma (smooth muscle) and rhabdomyosarcoma (skeletal muscle). Leiomyosarcomas are found in the abdomen, uterus or pelvis. Rhabdomyosarcomas are found in striated muscles that can be located anywhere in the body.
Dermatomyositis
Dermatomyositis is a disease of the muscle system that presents as a dusky red rash. The rash is most often on the eyelids, knuckles, face, chest, knees and back. Another sign of dermatomyositis is progressive symmetrical muscle weakness along the trunk line---thighs, hips, upper arms, shoulders and neck. Other signs may include muscle pain, fatigue, difficulty swallowing and ulcers, according to the Mayo Clinic.
Polymyositis
Polymyositis, an uncommon connective tissue disease, presents with muscle inflammation and skeletal muscle system weakness. According to Merck Manual, it is diagnosed most often in adults from 40 to 60 years of age or in children ages 5 to 15 years. Men are less likely to be affected than women. If polymyositis is associated with cancer, it can occur at any age.
