Muscular Dystrophy: Forms and How They Can Affect a Person
What is muscular dystrophy (“MD”)? According to the National Institute of Neurological Disorders and Stroke or NINDS, this medical problem is best understood as muscular dystrophies – a group of genetic diseases that is typified by progressive weakness and deterioration of the skeletal muscle of human beings (NIND, p.1). There are different types of MD, some are detected during infancy, others are detected only during childhood, while there are those that may not appear until the person is already in his or her middle-age or even later (NINDS, p.1). There are two important things that one must remember with regards to MDs.
First, it is a result of a genetic disorder that is usually hereditary (National Institute of Health, p.1). Secondly, it affects the skeletal muscles and therefore movement of the individual (Nielsen, p.155). This paper will take a closer look at the different forms of MDs and how they can affect the person suffering from this debilitating disease.
Scientists were able to identify that there are around 600 types of muscles in the body (Davis, King & Schultz, p.39). Muscles take up 40% of the person’s body weight (Davis, King & Schultz, p.39). There are two kinds of muscles; there skeletal muscles responsible for voluntary movement and there are smooth muscles that are responsible for involuntary movements such as those found on gastrointestinal tract and blood vessels (Davis, King & Schultz, p.39). But the concern of this study is the skeletal muscles. Whenever there is evidence of MD there is a weakening and degeneration of the skeletal muscles and thereby hampering voluntary movement (NINDS, p.1). The capabilities that normal people had taken for granted are not possible for someone who suffers from MD.
It is a type of disease that must not be confused with multiple sclerosis because it is not an acquired disease (Nielsen, p.155). It is inherited and passed on from one generation to the next (Nielsen, p.155). If the family tree shows signs of MD then there is a greater probability that the younger generation will also have MD. In recent studies it was estimated that at least 200,000 Americans from all ages and all backgrounds suffer from some form of MD (Nielsen, p.155). However, there are those who already have the genetic disposition to express MD but they do not know the symptoms and may not be prepared to cope with this life-altering disease.
Aside from the debilitating nature of muscular dystrophies, there is another dreadful feature of this disease: it has no cure (NINDS, p.1). According to experts, there is no specific treatment that can cure or reverse the effect of any type of muscular dystrophies (NINDS, p.1). Nevertheless, treatment may include physical therapy; respiratory therapy; speech therapy; orthopedic therapy; orthopedic appliances or equipment that can be used to support the patient; and corrective orthopedic surgery (NINDS, p.1).
Before going any further it is important to point out that there are different types of MDs listed as follows: a) Facioscapulohumeral Muscular Dystrophy; b) Limb-Girdle Muscular Dystrophy; Duchenne Muscular Dystrophy; Becker’s Muscular Dystrophy; Ocular Dystrophy; and Myotonic Dystrophy (Nielsen, p.155). The following is a more detailed description of the various types of MD.
Facioscapulohyumeral Muscular Dystrophy (“FSHD”) is the known to be the third most common inherited neuromuscular condition behind Duchenne and Myotonic Muscular Dystrophies (Cooper & Upadhyaya, p.1). The onset of the disease is usually detected after the age of 10 and even so, only five percent develop significant facial weakness (Cooper & Upadhyaya, p.1). It is not uncommon for symptoms to develop only after the 20th birthday of the affected individual (Cooper & Upadhyaya, p.1). The symptoms are progressive muscle weakness and atrophy of the muscles of the face, upper and shoulder girdle; and eventually, atrophy may also be present in the musculature of the pelvic girdle and the foot extensor (Cooper & Upadhyaya, p.1).
At the onset of the disease, the first thing that will be noticed is the atrophy of the face and shoulder girdle muscles but the effect might be minimal in the initial stages that is why it was said that some may not know they have the disease until way later, sometimes as late as early adulthood (Lovell & Winter, p.664). But for those who develop signs of the disease in infancy the following may be present: lack of mobility; incomplete eye closure, pouting lips with a slanting smile; and absence of eye and forehead wrinkles (Lovell & Winter, p.664). FSHD can occur in both males and females although studies show that the disease is more common in women (Lovell & Winter, p.664).
Limb-Girdle muscular dystrophy (“LGMD”) is differentiated from an FSHD in the lack of involvement in the facial muscles; instead, it affects the muscles of the hips and shoulders (Nielsen, p.155). The genetic abnormality has been described to be autosomal recessive and less frequently autosomal dominant and can be expressed in both males and females (Lopate, p.1). Symptoms of LGMD are usually evident in late childhood or even in the second decade of life (Nelsen, p.155). Just like FSHD, this type of muscular dystrophy progresses very slowly and yet when it is fully expressed the effect is severe (Nielsen, p.155). Within 20-30 years after diagnosis the individual usually suffers severe disability in the shoulder or pelvic-girdle muscles (Lopate, p.1).
Duchenne Muscular Dystrophy is the most common form of MD (Stone et al., p.1). It is also the most severe, however, it only appears in males (Nielsen, p.156). It derived its unique name from Dr. Duchenne de Boulogne, a mid-19th century French physician who was one of the first to study MDs (Stone et al., p.1). Roughly 1 in every 10,000 boys are affected with this type of MD and worse, one-third of those diagnosed with Duchenne are also believed to be mentally retarded as well (Nielsen, p.156). Signs of the disease can be detected early and oftentimes it manifest during the first three years of a boy’s life (Nielsen, p.156). Parents will observe their child have an uncertain gait, seems to lose balance and falls frequently and at the same time getting up from the floor and climbing the stairs will be a major challenge for him (Nielsen, p.156).
This is the direct result of a defective gene found on the X chromosome that causes the deficiency in the production of dystrophin – a protein needed to maintain the integrity of the muscle’s cell wall (Stone et al., p.1). When there is a deficiency there is an influx of calcium ions and then a breakdown of the calcium calmodulin complex and finally an excess amount of free radicals is released to the system (Stone et al., p.1). When these things happen there is an irreversible destruction of the muscle cells, specifically those in the hip-girdle muscles and the shoulder muscles (Stone et al., p.1).
Becker’s muscular dystrophy is very similar to the symptoms that one can find in Duchenne muscular dystrophy (NIH, p.1). The only major difference is that the person suffering from Becker’s dystrophy will experience the worse part of it at a slower rate (NIH, p.1). Another feature of this type of dystrophy is that it is highly hereditary and this simply means that if this medical condition is prevalent in the person’s medical history there is a high risk of acquiring Becker’s dystrophy (NIH, p.1).
In every population of 100,000 males there is a chance that 3-6 are born with this medical condition, however, it is less common than Duchenne muscular dystrophy (NIH, p.1). The muscle may sometimes appear bulky and the person suffering the disease may look muscular but this is only because the muscle that wasted away was now replaced with fat (Nielsen, p.156).
Ocular Dystrophy is also known as progressive external ophthalmoplegia, it is a rare form of MD (Lovell & Winter, p.664). The onset of the disease usually begins during the adolescent years (Lovell & Winter, p.664). This type of MD affects the eyes and throat (Nielsen, p.156). It specifically affects the extraocular muscles and will cause diplopia and ptosis (Lovell & Winter, p.664). There is a high probability that the individual will suffer double vision, drooping eyelids, and difficulty swallowing because of the deterioration of the muscles in the affected area (Nielsen, p.156).
Myotonic dystrophy is another rare type of MD and it affects the hands and feet. In addition, studies reveal that those who have myotonic dystrophy will not only experience progressive muscle weakness but also gonadal atrophy; cataracts; frontal baldness; heart disease, and even dementia (Lovell & Winter, p.665). The most common manifestation is the inability of the muscles to relax for several seconds after a forceful contraction (Nielsen, p.155). The onset of the disease usually occurs in late adolescence or early adulthood (Lovell & Winter, p.655).
The affected areas of the body are the quadriceps, hamstrings, and hip extensors (Lovell & Winter, p.655). In most cases the lower extremities are more affected as compared to the upper extremities (Lovell & Winter, p.655). Infants inflicted with this type of the disease are slow to develop (Nielsen, p.155).
There is no treatment available for those who suffer from muscular dystrophy (Nielsen, p.156). Nevertheless, children with MD must be encouraged to be physically active for it will ensure that the muscles will keep functioning as long as possible (Johanson, p.30). Dr. Alan Emery in his book Muscular Dystrophy the Facts does not recommend vigorous exercise or even strenuous calisthenics for those who suffer from MD (Johanson, p.30). The best advice, therefore, is moderate exercise and the best example is swimming because it promotes strength and flexibility (Johanson, p.30).
The hereditary nature of MD is already a significant factor to consider because it means that nothing can be done to prevent its occurrence. If a person’s medical history reveals muscular dystrophy then there is a higher chance that it will be expressed during his or her lifetime considering also that the onset for some of the rare forms does not occur until puberty or early adulthood. The best way to deal with it is therapy and to manage the disease in such a way that the quality of life may not be severely affected.
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Davis, Larry, Molly King, & Jessica Schultz. Fundamentals of Neurological Disease. New York: Demos Medical Publishing, 2005.
Johanson, Paula. Muscular Dystrophy. New York: Rosen Publishing Group, 2009.
Lopate, Glenn. “Limb-Girdle Muscular Dystrophy.” 2010. Web.
Lovell, Wood & Robert Winter. Lovell and Winter’s Pediatric Orthopaedics. Vol.1-2. PA: Lippincott, Williams and Wilkins, 2006.
National Institute of Health. “Becker Muscular Dystropy.” 2010. Web.
National Institute of Neurological Disorders and Stroke. “NINDS Muscular Dystrophy Information Page.” Web.
Nielsen, Lee Brattland. Brief Reference of Student Disabilities. CA: Corwin Press, 2009.
Stone, Kate et al. Occupational Therapy and Duchenne Muscular Dystrophy. New Jersey: John Wiley & Sons, 2007.