Muscular dystrophy

Overview

Muscular dystrophy (MD) refers to a group of genetic, hereditary muscle diseases that cause progressive muscle weakness. Muscular dystrophies are characterized by progressive skeletal muscle weakness, defects in muscle proteins, and the death of muscle cells and tissue. Nine diseases including Duchenne, Becker, limb girdle, congenital, facioscapulohumeral, myotonic, oculopharyngeal, distal, and Emery-Dreifuss are always classified as muscular dystrophy but there are more than 100 diseases in total with similarities to muscular dystrophy. Most types of MD are multi-system disorders with manifestations in body systems including the heart, gastrointestinal and nervous systems, endocrine glands, skin, eyes and other organs

Symptoms

Progressive Muscular Wasting (weakness) Poor Balance Frequent Falls Walking Difficulty Waddling Gait Calf Pain Limited Range of Movement Muscle Contractures Respiratory Difficulty Drooping Eyelids (ptosis) Gonadal atrophy Scoliosis (curvature of the spine) Inability to walk

Diagnosis

The diagnosis of muscular dystrophy is based on the results of a muscle biopsy. In some cases, a DNA blood test may be all that is needed. A physical examination and the patient's medical history will help the doctor determine the type of muscular dystrophy. Specific muscle groups are affected by different types of muscular dystrophy. Often, there is a loss of muscle mass (wasting), which may be hard to see because some types of muscular dystrophy cause a build up of fat and connective tissue that makes the muscle appear larger. This is called pseudohypertrophy.

Prognosis

The prognosis for people with muscular dystrophy varies according to the type and progression of the disorder. Some cases may be mild and progress very slowly over a normal lifespan, while others produce severe muscle weakness, functional disability, and loss of the ability to walk. Some children with muscular dystrophy die in infancy while others live into adulthood with only moderate disability. The muscles affected vary, but can be around the pelvis, shoulder, face or elsewhere. Muscular dystrophy can affect adults, but the more severe forms tend to occur in early childhood.

Treatment

There is no known cure for muscular dystrophy. Inactivity (such as bed-rest and even sitting for long periods) can worsen the disease. Physical therapy, Occupational therapy, speech therapy and orthopedic instruments (e.g., wheelchairs, standing frames) may be helpful. There is no specific treatment for any of the forms of muscular dystrophy. Physical therapy to prevent contractures (a condition when an individual with a muscular dystrophy grows and the muscles don't move with the bones and can easily be slowed down and/or make the individual's body straighter by daily physical therapy), orthoses (orthopedic appliances used for support) and corrective orthopedic surgery may be needed to improve the quality of life in some cases. The cardiac problems that occur with Emery-Dreifuss muscular dystrophy and myotonic muscular dystrophy may require a pacemaker. The myotonia (delayed relaxation of a muscle after a strong contraction) occurring in myotonic muscular dystrophy may be treated with medications such as quinine, phenytoin, or mexiletine but no actual long term treatment has been found. Occupational therapy assists the individual with MD in engaging in his/her activities of daily living (self-feeding, self-care activities, etc) and leisure activities at the most independent level possible. This may be achieved with use of adapted equipment or the utilization of energy conservation techniques. Occupational therapy may also implement changes to a person's environment, both at home or work, to increase the individual's function and accessibility. Occupational therapists also address psychosocial changes and cognitive decline which may accompany MD as well as provide support and education about the disease to the family and individual