What Are the Different Types of Muscular Dystrophy?

Muscular dystrophy (MD) is an inherited disorder that causes muscle weakness and atrophy. There are nine main types of muscular dystrophy, some with subtypes. Muscular dystrophy symptoms are similar through all types.

Each type of MD causes weakness and degeneration of the muscles involved in voluntary movement, such as walking. All types of MD are progressive, but they vary by age of onset, severity, and the pattern in which the muscles are affected.

The most common type of MD is Duchenne muscular dystrophy. Typically, Duchenne MD becomes apparent during the toddler years as children begin to walk. Other types of MD, like Becker MD, may appear later in childhood or even in people up to the age of 25.

Some other types of MD, like oculopharyngeal MD, do not appear until you are well into adulthood, generally beginning in your 40s or 50s.

While there is currently no cure for muscular dystrophy, there is much hope. Advances in treatments to manage disease progression and symptoms have improved life expectancy over the last century.

Ongoing research in treatments is promising. In 2003 the National Institute of Health (NIH) established a research program to focus solely on muscular dystrophy—its causes and potential treatments. Each of the nine types of MD is being studied as well.

Duchenne

Duchenne muscular dystrophy (DMD) usually appears early in childhood between the ages of 2 and 3. DMD primarily affects boys but can affect girls in rare cases. The primary symptom of DMD is muscle weakness that begins in the muscles close to the body and later affects muscles in the outer limbs.

Most often, the muscles in the lower limbs are affected before the upper limbs. Children with Duchenne MD will often have difficulty running, walking, or jumping. They may have a waddle in their gait or enlarged calves.

Later in the progression of the disease, the heart and respiratory muscles can be affected, causing difficulty breathing and eventually acute respiratory failure.

When DMD was first discovered, life expectancy was low. Most people did not survive past their teen years. However, with advancements in cardiac and respiratory care, many people with DMD can now expect to live into early adulthood. With treatments and managed care, it is possible to live into your 30s with DMD.

Becker

Becker muscular dystrophy typically becomes apparent between the ages of 5 and 15. It is similar to Duchenne MD, except that it progresses slower and symptoms begin to appear later. Boys are primarily affected by Becker MD.

Becker MD causes muscle loss that begins in the hips and pelvic area, thighs, and shoulders. To compensate for weakening muscles, those with Becker MD may start to walk on their toes, stick out their abdomen, or walk with a gait.

Most people with Becker MD will develop weakened muscles in their heart. Sometimes this can be the most prominent symptom and can lead to heart failure.

If heart problems are minimal or controlled through medical management, people with Becker MD can expect to have a near-normal lifespan. However, the most common cause of death for those with BMD is heart failure, and the mean life expectancy with heart involvement is the mid-40s.

Limb-Girdle

There are over 30 forms of limb-girdle muscular dystrophy (LGMD). Each form or subtype is classified by the affected genes and affects men and women. The most prevalent forms are caused by recessive inheritance.

The age of onset of limb-girdle muscular dystrophy is highly varied, ranging from early childhood to later adulthood. The disease is characterized by muscle weakness and atrophy of the muscles of the hip and shoulder areas (the limb girdles).

Most cases of LGMD affect the muscles of the hip and pelvis first, causing symptoms such as difficulty standing or walking up stairs or a waddling gait. Eventually, the muscles of the shoulder areas become affected, causing symptoms such as difficulty raising arms overhead or carrying heavy objects.

Some forms of LGMD can cause cardiomyopathy or weakness in the heart muscle. In other forms, the respiratory system muscles can be affected, causing breathing difficulties or difficulty swallowing.  

The outlook for those living with LGMD is highly varied. Generally, the earlier the age of onset, the more progressive and severe the disease tends to be.

In those with adult-onset LGMD, progression tends to be slower with milder symptoms. Most people can expect to live into adulthood. However, life expectancy tends to be lower than average.

Myotonic

Myotonic dystrophy (DM) affects the muscles and other bodily systems in both males and females. There are two types of DM, type 1 and type 2. DM type 1 (DM1) is classified even further as mild or classic.

In mild DM1, symptoms include cataracts, a clouding of the lenses of the eyes, and muscle contractions that do not subside (myotonia). With myotonia, you may grip a door handle and be unable to release it.

Classic DM1 is characterized by muscle weakness and atrophy, along with early-onset cataracts and heart abnormalities. You can also experience problems of the gastrointestinal system, causing abdominal pain, pseudo obstructions where the muscles stop moving food through the GI tract, or gallstones.

Men may have changes in hormones that cause balding or infertility.

The most common form of DM is adult-onset DM1 and usually begins in a person’s 30s. Juvenile DM1 usually occurs around age 12, and those who show signs of DM1 at birth have congenital DM, which is the most severe.

DM type 2 (DM2) is similar to DM1 but is generally less severe. Myotonic dystrophy type 2 typically occurs in the 30s but can appear as early as someone’s 20s and as late as someone’s 60s.

The life expectancy of living with DM varies depending on the type of DM and the medical problems present. Typically, those with the mild form of DM1 can expect a normal life expectancy.

Facioscapulohumeral

Facioscapulohumeral dystrophy (FSHD) typically appears before the age of 20, but can appear later in adulthood or even in childhood in both males and females. FSHD affects the muscles of the face, around the shoulder blades, and in the upper arms.

Symptoms of FSHD include facial weakness that can make it difficult to move the lips, causing problems like being unable to use a straw.

If the upper facial muscles are affected, you may be unable to completely close your eyes while sleeping. Decreased ability to raise the arms can also occur, along with sagging collarbones and shoulder blades that have a prominent appearance.

Most people with FSHD will experience asymmetrical weakness of their muscles, meaning one side of the body will be affected differently than the other.

Progression of FSHD is typically slow, and some people may never experience symptoms. Those with FSHD have a normal life expectancy.

Congenital

Congenital muscular dystrophy (CMD) occurs at or near birth. There are at least 30 different types of CMD characterized by the muscles and body systems that are affected, such as CMD with adducted thumbs and ophthalmoplegia (paralyzed eye muscles) and intellectual disability, CMD with cardiomyopathy, and CMD with spinal rigidity.

Babies born with CMD are often characterized as “floppy” due to muscle weakness. They may have fixed joints and difficulty reaching certain milestones, such as sitting up. In some types of CMD, the brain may be affected, causing intellectual disability.

Life expectancy with CMD is dependent on the type and progression. Some babies will die in infancy, and others can live well into adulthood.

Oculopharyngeal

Oculopharyngeal muscular dystrophy (OPMD) onset usually occurs during adulthood between the ages of 40 and 60 and affects males and females equally. The most common early symptoms of OPMD are drooping of the upper eyelids and difficulty swallowing.

In those whose eyelids have been affected, they may tilt their head back to see if their eyelids are obstructing their sight.

Some people may experience degeneration of the muscles of the upper legs as the disease progresses. This can affect the ability to walk, kneel, or climb stairs and be mild or severe. About 10% of people with OPMD will need a wheelchair.

Progression of OPMD is generally slow, and life expectancy is normally not shortened.

Distal

Distal muscular dystrophy, or distal myopathy, typically appears between the ages of 40 and 60 and affects both men and women. Distal MD affects the muscles in the forearms, hands, lower legs, and feet. There are at least 11 subtypes of distal MD characterized by the muscles affected.

In Welander distal myopathy, muscles of the hands, feet, toes, and fingers are affected. Udd distal myopathy affects the muscles around the ankle and can spread to those of the shinbone. Over time this can cause foot drop, or the inability to turn the feet and toes upward. The other subtypes affect different muscles.

Progression of distal muscular dystrophy is usually very slow and is not considered to affect life expectancy.

Emery-Dreifuss

Emery-Dreifuss muscular dystrophy usually appears by the age of 10, but can appear in someone’s 20s. Boys are most affected by Emery-Dreifuss MD, but females can be carriers of the disorder.

Emery-Dreifuss MD is marked by slow but progressive wasting of the muscles of the upper arms and legs. Contractures of the spine, ankles, knees, and elbows usually occur before significant muscle weakness.

Most people with Emery-Dreifuss MD have some sort of heart problem by the age of 30 that usually requires a pacemaker or other assistive medical device. Those affected by the disease often die in mid-adulthood from cardiac or pulmonary failure.

A Word From Verywell

While a diagnosis of muscular dystrophy for yourself or a loved one can feel scary, know that there are many resources to help you manage life with muscular dystrophy. The Muscular Dystrophy Association is a great place to start, but your healthcare provider can also help give you direction. Don’t be afraid to ask for help if you are struggling.

Current research promises a brighter future. Whether you or your child lives with one of the nine types of muscular dystrophy, you can be assured that advancements in understanding the disease and how to treat it are being made.

Ongoing research provides hope that quality of life and life expectancy with any type of muscular dystrophy will continue to improve.