Duchenne muscular dystrophy Health Dictionary

See MUSCLES, DISORDERS OF – Myopathy.... muscular dystrophy

Dystrophy means defective or faulty nutrition, and is a term applied to a group of developmental changes occurring in the muscles, independently of the nervous system (see MUSCLES, DISORDERS OF). The best-known form is progressive muscular dystrophy, a group of hereditary disorders characterised by symmetrical wasting and weakness, with no sensory loss. There are three types: Duchenne (usually occurring in boys within the ?rst three years of life); limb girdle (occurring in either sex in the second or third decade); and facio-scapulohumeral (either sex, any age). The three types have di?erent prognoses, but may lead to severe disability and premature death, often from respiratory failure. The third type progresses very slowly, however, and is compatible with a long life.

Diagnosis may be con?rmed by ELECTROMYOGRAPHY (EMG) or muscle biopsy. Although genetic research is pointing to possible treatment or prevention, at present no e?ective treatment is known, and deterioration may occur with excessive con?nement to bed. Physio-therapeutic and orthopaedic measures may be necessary to counteract deformities and contractures, and may help in coping with some disabilities.... dystrophy

A condition in which certain muscles enlarge owing to a fatty and ?brous degeneration, giving a false appearance of increased strength.

Pseudomonas Aeruginosa

A pathogenic bacterium of the genus pseudomonas – rod-like, motile gram-negative bacteria (see GRAM’S STAIN) – that occurs in pus from wounds and is associated with urinary tract infections. The bacteria mostly live in soil and decomposing organic matter and help to recycle nitrogen in nature. Most of the bacteria in this genus are harmless to humans.... pseudohypertrophic muscular dystrophy

The muscles of the body that are attached to the skeleton. These muscles are responsible for voluntary movement, and also support and stabilize the skeleton. In most cases, a muscle attaches to a bone (usually by means of a tendon) and crosses over a joint to attach to another bone. Muscles can produce movement by contracting and shortening to pull on the bone to which they are attached. They can only pull, not push, and are therefore arranged so that the pull of one muscle or group of muscles is opposed to another, enabling a movement to be reversed. Although most actions of the skeletal muscles are under conscious control, reflex movements of certain muscles occur in response to stimuli.

There are more than 600 muscles in the body, classified according to the type of movement they produce.

An extensor opens out a joint, a flexor closes it; an adductor draws a part of the body inwards, an abductor moves it outwards; a levator raises it, a depressor lowers it; and constrictor or sphincter muscles surround and close orifices.... muscular system

A rare, inherited disorder characterized by muscle wasting in the feet and calves and then in the hands and forearms.

The condition, also known as Charcot–Marie– Tooth disease, is caused by degeneration of some peripheral nerves.

It is more common in boys, and usually appears in late childhood or adolescence.

Muscle wasting stops halfway up the arms and legs, making them look like inverted bottles; sensation may be lost.

There is no treatment, but the sufferer rarely becomes totally incapacitated because the disease usually progresses very slowly.

Life expectancy is normal.... peroneal muscular atrophy

A type of motor neuron disease in which the muscles of the hands, arms, and legs become weak and wasted and twitch involuntarily. The condition eventually spreads to other muscles.... progressive muscular atrophy

a *sex-linked (X-linked) disorder in which affected males develop an increase in muscle size followed by weakness and wasting. It usually starts between the ages of 5 and 15, and 25 years after onset most patients are wheelchair-bound. Although most men become severely disabled, life expectancy is close to normal. The disorder is similar to Duchenne *muscular dystrophy but less severe. [P. E. Becker (20th century), German geneticist]... becker muscular dystrophy

a hereditary condition in which the corneal endothelium loses its functional ability, usually with age. It may result in thickening and swelling of the cornea (*bullous keratopathy) and thus affect vision. Cornea guttata, small whitish deposits of hyalin, are seen on the inner surface of the cornea and signify a reduced number of endothelial cells. A corneal transplantation (see keratoplasty) may become necessary in certain cases. [E. Fuchs (1851–1913), German ophthalmologist]... fuchs’ endothelial dystrophy

any aching pain in the muscles and joints. Commonly the symptoms are due to *fibrositis; wear and tear of the joints (*osteoarthritis); or to inflammation of the muscles associated with abnormal immune reactions (*polymyalgia rheumatica). Generalized muscle pain with specific tender points and fatigue is called *fibromyalgia.... muscular rheumatism

see complex regional pain syndrome.... reflex sympathetic dystrophy

(SMA) a hereditary condition in which cells of the spinal cord die and the muscles in the arms and legs become progressively weaker. Eventually the respiratory muscles are affected and death usually results from respiratory infection. Most affected individuals are wheelchair-bound by the age of 20 and few survive beyond the age of 30. The gene responsible has been located: in affected children it is inherited as a double *recessive. There are three forms of the disease, based on severity of the symptoms and the age at which they appear. Type 1 (infantile spinal muscular atrophy) is the most acute and aggressive form of the condition (see Werdnig–Hoffmann disease). Type 2 develops between the ages of 6 months and 2 years and type 3 (Kugelberg–Welander disease), the least severe form, appears between 2 and 17 years of age.... spinal muscular atrophy