limb girdle muscular dystrophy

Advocacy Project

Limb girdle muscular dystrophy

Limb girdle muscular dystrophy is a disesase that casue's your body to weaken and break down. This disease can cause many adults and children to die and a young age.

LGMD is caused by a mutation in any of at least 15 different genes that affect proteins necessary for muscle function. Some types are autosomal dominant, meaning LGMD is inherited from one parent. Other types are autosomal recessive and occur when a faulty gene is inherited from each parent.

Over time, muscle weakness and atrophy can lead to limited mobility and an inability to raise the arms above the shoulders. The involuntary muscles, except for the heart (which is a special type of involuntary muscle), aren't affected in LGMD. Digestion, bowel, bladder and sexual function remain normal.

What is limb-girdle muscular dystrophy?

Limb-girdle muscular dystrophy (LGMD) isn’t really one disease. It’s a group of disorders affecting voluntary muscles, mainly those around the hips and shoulders. The shoulder girdle is the bony structure that surrounds the shoulder area, and the pelvic girdle is the bony structure surrounding the hips. Collectively, these are called the limb girdles, and it is the muscles connected to the limb girdles that are the most affected in LGMD.

The term proximal is also used to describe the muscles that are most affected in LGMD. The proximal muscles are those closest to the center of the body; distal muscles are farther away from the center (for example, in the hands and feet). The distal muscles are affected late in LGMD, if at all.

As of late 2012, there are more than 20 different subtypes of LGMD, and this is a complex and constantly evolving area of research. See the table below for a more complete list of the LGMD subtypes.

What is the progression of LGMD?

At this time, progression in each type of LGMD can’t be predicted with certainty, although knowing the underlying genetic mutation can be helpful. Some forms of the disorder progress to loss of walking ability within a few years and cause serious disability, while others progress very slowly over many years and cause minimal disability.

LGMD can begin in childhood, adolescence, young adulthood or even later. Both genders are affected equally.

When limb-girdle muscular dystrophy begins in childhood, some physicians say, the progression is usually faster and the disease more disabling. When the disorder begins in adolescence or adulthood, they say, it’s generally not as severe and progresses more slowly.

Signs and Symptoms

Often, people with LGMD first notice a problem when they begin to walk with a “waddling” gait because of weakness of the hip and leg muscles. They may have trouble getting out of chairs, rising from a toilet seat or climbing stairs.

Weakness in the shoulder area may make reaching over the head, holding the arms outstretched or carrying heavy objects difficult. It may become increasingly hard to keep the arms above the head for such activities as combing your hair or arranging things on a high shelf. Some people find it harder to type on a computer or other keyboard and may even have trouble feeding themselves.

Assistive devices, such as a cane or a long-handled reacher, can make things easier as weakness progresses.

A power wheelchair or scooter becomes convenient when weakness in the pelvic girdle and upper legs causes frequent falls. People whose LGMD has reached this stage often find that a great deal of their independence returns, and they’re much less fatigued, when they begin using this type of vehicle.

The heart can be affected in LGMD, but this doesn’t occur as often as it does in some other forms of muscular dystrophy. Heart problems can take two forms — weakness of the heart muscle (cardiomyopathy) and abnormal transmission of signals that regulate the heartbeat (conduction abnormalities or arrhythmias). The heart should be monitored for these complications. When necessary, medications or devices (such as pacemakers) can be used to treat them.

Respiratory (breathing) function can decline over time, and this, too, should be monitored regularly. There are devices that can help sustain respiratory function.

LGMD, like other muscular dystrophies, is primarily a disorder of voluntary muscles. These are the muscles you use to move the limbs, neck, trunk and other parts of the body that are under voluntary control.

The involuntary muscles, except for the heart (which is a special type of involuntary muscle), aren’t affected in LGMD. Digestion, bowel and bladder functions and sexual function, which are carried out by involuntary muscles, remain normal.

Pain isn’t a major part of LGMD, although limited mobility sometimes leads to muscle soreness and aching joints.

Exercises to keep joints limber, moving around as much as possible, warm baths and, if needed, medication can keep this kind of discomfort to a minimum.

The brain, the intellect and the senses are unaffected in LGMD. People with LGMD can think, see, hear and feel sensations as well as those without muscular dystrophy.

Assistive devices

Simple devices like a cane or a long-handled reacher can make things easier as weakness progresses.

A power wheelchair or scooter becomes convenient when weakness in the pelvic girdle and upper legs causes frequent falls. People whose LGMD has reached this stage often find that a great deal of their independence returns, and they’re much less fatigued when they begin using this type of mobility equipment.

Therapy and exercise

Physical and occupational therapy programs are usually part of the treatment for LGMD. Occupational therapy focuses on specific activities and functions, particularly use of the hands, while physical therapy emphasizes mobility and (where possible) strengthening of large muscle groups. Your MDA clinic physician may refer you to the therapy department at your medical center for a thorough evaluation and an individualized exercise program.

The primary goals of physical therapy are to allow greater motion in the joints and to prevent contractures (freezing of the joints). These problems can arise when movement is limited, and it’s important for the patient’s comfort and function to avoid them.

In occupational therapy, the focus is on improving abilities related to your job, recreation or daily living. For example, arm supports can make tasks such as using a computer or fixing your hair less tiring.

Doctors and therapists have somewhat different opinions on the relative value or danger of various exercise regimens in people with muscular dystrophy. In LGMD, certain kinds of stress-causing exercises may actually hasten muscle damage.

Some experts recommend swimming and water exercises as a good way to keep muscles as toned as possible without causing undue stress on them. The buoyancy of the water helps protect against certain kinds of muscle strain and injury. Before undertaking an exercise program, make sure you’ve had a cardiac evaluation, and don’t swim alone. For more on exercise, see Exercising with a Muscle Disease.

Nondrug treatment

Physiotherapy to prevent contractures, using passive stretching, exercise therapy, ± orthoses.[13]

Exercise - the role of exercise in LGMD is controversial, but guidelines for other types of muscular dystrophy suggest gentle exercise within limits of comfort, and avoidance of prolonged immobility.

Occupational therapy and aids such as a wheelchair, with careful attention to seating so as to minimise the development of scoliosis.

Genetic counselling.

Advice on benefits.

Support groups (eg, Muscular Dystrophy Campaign).

Monitoring for complications (see 'Complications and their Management', below).

Possible drug treatment

Corticosteroids have been used in some patients with LGMD 2C-F, giving improvement in some reported cases.[2][14]

A study involving two patients with dysferlin-deficient muscular dystrophy reported an improvement in muscle strength after treatment with rituximab.[15]


Throughout the 1990s and the first decade of the 21st century, MDA-supported researchers identified dozens of genes that, when defective, cause LGMD.

This gene identification work continues to the present day, along with research to determine the precise function of these genes so that missing functions can be compensated for and toxic functions can be inhibited.

In the recessive forms of LGMD, it may be possible to insert a new gene to compensate for one that isn’t working properly. This type of intervention — gene therapy — has shown promise in a pilot trial in people with the alpha-sarcoglycan-deficient form of LGMD.

In the dominant forms of LGMD, blocking a toxic function using strategies such as "antisense," which keep cells from interpreting genetic information, may become a treatment in the future.

Some genetic mutations, known as “premature stop codons,” cause cells to stop reading genetic instructions before a fully functional protein has been synthesized. A drug that causes cells to “read through” these stop codons is being tested in another form of muscular dystrophy (Duchenne) and may have some application in LGMD.

Some genetic mutations add or remove DNA and change the way cells interpret the information in a gene. In Duchenne muscular dystrophy, clinical trials are under way of compounds that coax cells to snip out these error-containing DNA regions (exon skipping); this research also may have relevance for LGMD treatment.

Still another strategy is to use stem cells to help ailing muscles regain strength. Stem cells are early-stage, flexible cells that can give rise to mature muscle fibers. They're found in muscle tissue and other places in the body, and scientists are working to determine which cells are the safest and most effective to test in people with LGMD and other diseases.

An additional avenue of investigation is blocking a natural protein called myostatin, which puts a brake on muscle growth.

To read the most current news about any of the research strategies mentioned here, use the MDA search box found at the top of this page.

To learn more, read In Focus: Limb-Girdle Muscular Dystrophy (October 2013 special report).

Limb Girdle Muscular Dystrophy

The Limb Girdle muscular dystrophies (LGMD) comprise at least a dozen different specific entities. Each of these distinct disorders is in itself rare. Patients with LGMD usually begin to have symptoms in adolescence or early adulthood, however, some forms of LGMD are more severe with symptoms beginning in childhood. Typically, these symptoms include weakness in the shoulders, hips, upper arms and legs. For example, patients may have progressive difficulty lifting or climbing stairs. In some forms of LGMD, the heart muscle is also affected. Although LGMD is inherited, there is frequently no family history of this disorder.

Diagnosis and Treatment

The diagnosis of LGMD is based on the clinical history, including a possible family history, physical examination and supporting laboratory studies. For some of the LGMDs, it is possible to make a definitive diagnosis by a blood test to determine the specific genetic defect responsible for symptoms. Our genetics counselor will carefully review the history of disease with each family, discuss the principles of inheritance and help weigh risks and benefits of genetic testing of various family members. In other situations, additional laboratory studies are necessary to make a diagnosis including electrodiagnostic testing (EMG) and muscle biopsy. Muscle biopsy is often helpful to determine if weakness is caused by muscular dystrophy, an inherited disorder, or by other acquired causes of muscle degeneration such as from inflammation or toxic exposure.

Treatment of LGMD is by a multidisciplinary team. A neurologist oversees the various needs of the patient and directs care. Specialists in rehabilitation medicine are present during the MDA clinic to meet with patients and provide individualized exercise and stretching programs for the treatment of weakness and contractures. Also on the same day, the patient will be evaluated for the need for splints and orthotics to help with hand or foot function. Equipment needs as well as social and financial needs are addressed. Other services, such as from an orthopedic surgeon, for further treatment of contractures or scoliosis, or from a cardiologist, for the treatment of cardiomyopathy or cardiac arrhythmias, are available as needed and are provided by physicians with special interest and expertise in MDA diagnoses.

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