Muscular Dystrophy: Types, Symptoms, Causes, Diagnosis, Treatment, and Outlook

Article Summary

Muscular dystrophy is a group of genetic diseases that cause muscles to become weaker over time. Different types affect different muscles and can begin in childhood or adulthood. Some mainly affect movement, while others can also affect the heart, breathing, swallowing, or other parts of the body. Muscular dystrophy is caused by changes in genes needed for healthy muscle function. Diagnosis often involves blood tests and genetic testing, with other tests used when needed. There is no single cure for all muscular dystrophies, but treatment can protect movement, manage complications, and improve quality of life and, in some forms, slow disease progression.

Cite as: Muscular Dystrophy: Types, Symptoms, Causes, Diagnosis, Treatment, and Outlook. Brisbane (AU): Exon Publications; 2024 Apr 23 [updated 2026 Aug 19].

Introduction

Muscular dystrophy is not one disease. It is a large group of inherited muscle disorders that differ in their genetic causes, age of onset, muscles affected, and rate of progression. The common feature is ongoing damage to muscle fibers, which leads to muscle weakness and loss of muscle tissue over time (1). Some forms cause serious disability early in life, while others develop slowly and may remain relatively mild for many years.

What Is Muscular Dystrophy?

Muscles are made of fibers that need many different proteins to remain strong and repair everyday damage. In muscular dystrophy, a change in a gene interferes with one of these proteins or another process needed for healthy muscle function. Muscle fibers become damaged and are gradually replaced by fat and scar-like tissue (1).

Different muscular dystrophies involve different genes and proteins. Duchenne and Becker muscular dystrophy involve the protein dystrophin, but lack of dystrophin is not the cause of muscular dystrophy as a whole. Other forms result from changes affecting completely different proteins and cell processes (1).

The pattern of weakness often provides clues to the type of muscular dystrophy. Some forms mainly affect the hips and shoulders, while others begin in the face, lower legs, hands, eyelids, or throat muscles.

What Are the Main Types of Muscular Dystrophy?

There are many forms of muscular dystrophy. The major groups include the following (1).

Duchenne muscular dystrophy (DMD) usually begins in early childhood and mainly affects boys because it is caused by a change in the DMD gene on the X chromosome. Muscle weakness usually starts around the hips and legs and gradually spreads. The heart and breathing muscles can also be affected.

Becker muscular dystrophy is also caused by changes in the DMD gene, but some working dystrophin is usually produced. Symptoms often begin later and progress more slowly than in Duchenne muscular dystrophy.

Limb-girdle muscular dystrophy (LGMD) is a genetically diverse group of disorders that mainly weaken muscles around the hips and shoulders. More than 30 genetic forms are recognized, and some can also affect the heart or breathing muscles (2).

Facioscapulohumeral muscular dystrophy (FSHD) mainly affects muscles of the face, shoulder blades, and upper arms. Weakness can be uneven, with one side of the body more affected than the other. Genetic testing for FSHD differs from routine testing for many other muscular dystrophies because the underlying genetic changes are unusual (3).

Myotonic dystrophy causes muscle weakness together with myotonia, which means muscles have difficulty relaxing after they contract. It is a multisystem disorder and may also affect the heart, eyes, digestive system, hormones, sleep, and other body functions (1).

Congenital muscular dystrophies begin at birth or during infancy. They include several genetic disorders with widely different effects on muscles, movement, the brain, eyes, and other organs.

Other forms include Emery-Dreifuss muscular dystrophy, distal muscular dystrophies, and oculopharyngeal muscular dystrophy. Their patterns of weakness and associated complications differ.

What Causes Muscular Dystrophy and How Is It Inherited?

Muscular dystrophies are caused by disease-causing changes in genes involved in muscle structure, repair, or function. The exact gene depends on the type of muscular dystrophy (1, 2).

Some forms are X-linked, meaning the altered gene is on the X chromosome. Duchenne and Becker muscular dystrophy are examples. They mainly affect boys and men, although girls and women who carry a DMD gene change can sometimes develop muscle or heart problems.

Other muscular dystrophies may be autosomal dominant, meaning one altered copy of a gene can cause the condition, or autosomal recessive, meaning altered copies are usually inherited from both parents.

A person can also develop muscular dystrophy because of a new genetic change that was not inherited from either parent. This is called a de novo change. The parents did not cause the genetic change.

Once the specific genetic cause is known, genetic counseling can help a family understand how the condition may have been inherited, whether other relatives could be affected, and the chance of passing it to future children.

What Are the Symptoms of Muscular Dystrophy?

Progressive muscle weakness is the main feature of muscular dystrophy, but the pattern varies greatly between types (1).

Possible symptoms include difficulty running, climbing stairs, rising from the floor, lifting the arms, or carrying objects. A child may fall frequently, walk on the toes, or develop a waddling walk. Some people develop weakness of the face, hands, lower legs, eyelids, or swallowing muscles instead of the more familiar hip and shoulder weakness.

Muscles and tendons may become tight, producing contractures that limit movement at a joint. Weakness around the spine can contribute to scoliosis, an abnormal sideways curve of the spine.

Some muscular dystrophies affect more than skeletal muscles. Heart muscle disease or abnormal heart rhythms can occur in several forms. Weak breathing muscles may reduce the ability to take deep breaths or cough effectively. Swallowing problems can make eating difficult and increase the risk of food entering the airway (4, 5).

The presence of these complications depends on the particular muscular dystrophy. A person should not assume that complications associated with one type will occur in every other type.

How Is Muscular Dystrophy Diagnosed?

Diagnosis begins with the pattern of muscle weakness, the age when symptoms started, medical history, and family history. A neurological examination looks at muscle strength, movement, reflexes, walking, and other physical signs (1).

A blood test for creatine kinase (CK) is often useful. CK is an enzyme found inside muscle cells. When muscle fibers are damaged, CK enters the bloodstream. Very high CK levels can suggest a muscle disease, but CK alone cannot identify the exact type of muscular dystrophy.

Genetic testing has become central to diagnosis. It can identify the disease-causing genetic change in many people and may provide a precise diagnosis without a muscle biopsy. The testing method depends on the suspected disorder because different muscular dystrophies involve different kinds of genetic changes (2, 3).

A confirmed genetic diagnosis can also help doctors estimate possible complications, guide testing of relatives, provide information for genetic counseling, and determine whether a person may be eligible for a treatment aimed at a particular genetic change (2).

Other tests may be used when the diagnosis remains unclear. These can include electromyography, which measures electrical activity in muscles, magnetic resonance imaging (MRI) of muscles, heart tests, breathing tests, and sometimes a muscle biopsy. A biopsy involves removing a small sample of muscle for examination in a laboratory.

How Is Muscular Dystrophy Treated and Managed?

Treatment depends on the exact type of muscular dystrophy and the problems it causes. There is no single treatment that cures all forms. Modern care focuses on maintaining function, preventing avoidable complications, treating problems early, and using disease-specific therapies when available (4-6).

Physical therapy and stretching help maintain movement and reduce contractures. Exercise needs to be adapted to the person's condition because excessive strain on already vulnerable muscles may be harmful. Orthoses, walking aids, wheelchairs, and other mobility equipment can support independence when needed.

Occupational therapy helps people adapt everyday activities such as dressing, bathing, writing, working, and using computers. Equipment and changes to the home, school, or workplace can reduce physical effort.

Medicines depend on the muscular dystrophy. Corticosteroids and related medicines can slow loss of muscle function in Duchenne muscular dystrophy. Newer treatments include drugs that act on particular genetic changes or biological pathways involved in DMD (4, 6).

Gene-based treatments are developing rapidly, particularly for Duchenne muscular dystrophy. Exon-skipping medicines can help some people with specific DMD gene changes, while gene therapy aims to provide muscle cells with genetic instructions for producing a shortened but functional form of dystrophin. These treatments are not suitable for every person, and availability and eligibility vary by genetic change, country, age, disease stage, and current regulatory guidance (6).

Heart care is essential in forms that can damage the heart. Regular electrocardiograms, echocardiograms, cardiac MRI scans, or other tests may detect problems before symptoms become obvious. Medicines can be used to protect heart function when needed (5).

Breathing care may include regular lung-function testing, assisted coughing, treatment of sleep-related breathing problems, and noninvasive ventilation when breathing muscles become weak (5).

Nutrition, swallowing therapy, speech therapy, psychological support, pain management, and orthopedic care may also form part of treatment. Surgery is sometimes used for severe contractures, scoliosis, or other complications.

Because muscular dystrophy can affect several body systems, people with more complex forms often benefit from coordinated care involving neurology, rehabilitation, cardiology, respiratory medicine, physiotherapy, genetics, and other specialties (4, 5).

What Is the Outlook for People With Muscular Dystrophy?

The outlook varies greatly because muscular dystrophy includes many different diseases. Some forms begin in infancy and progress rapidly, while others appear in adulthood and cause relatively slow changes over decades (1).

The genetic subtype, muscles and organs affected, age at onset, and access to appropriate care all influence how the condition develops. Heart or breathing complications can have a major effect on health in some forms, which is why regular monitoring is important even when a person feels well.

Advances in respiratory care, heart treatment, rehabilitation, and multidisciplinary management have changed the course of conditions such as Duchenne muscular dystrophy. Disease-modifying and gene-based therapies are also expanding treatment options, although their long-term effects and availability differ between treatments and countries (4-6).

A population statistic cannot predict exactly what will happen to an individual. The most useful outlook comes from knowing the precise muscular dystrophy subtype and following the person's health and function over time.

Conclusion

Muscular dystrophy is a group of genetic diseases that cause progressive muscle weakness, but the causes, symptoms, and severity differ widely between types. Duchenne and Becker muscular dystrophy involve dystrophin, while other muscular dystrophies result from changes in many different genes. Genetic testing is now central to diagnosis and can guide family counseling, monitoring, and sometimes treatment. Management may include physical and occupational therapy, medicines, mobility support, heart and breathing care, and disease-specific therapies. Identifying the exact type is important because it helps determine which complications should be monitored and which treatments may be useful.

References

1. Mercuri E, Bönnemann CG, Muntoni F. Muscular dystrophies. Lancet. 2019;394(10213):2025-2038. https://doi.org/10.1016/S0140-6736(19)32910-1


2. Straub V, Clause AR, Donkervoort S, et al. Expert consensus on genetic diagnostic approaches for patients with limb-girdle muscular dystrophy. Neurology. 2025;105(10):e214291. https://doi.org/10.1212/WNL.0000000000214291


3. Giardina E, Camaño P, Burton-Jones S, et al. Best practice guidelines on genetic diagnostics of facioscapulohumeral muscular dystrophy: Update of the 2012 guidelines. Clin Genet. 2024;106(1):13-26. https://doi.org/10.1111/cge.14533


4. Birnkrant DJ, Bushby K, Bann CM, et al. Diagnosis and management of Duchenne muscular dystrophy, part 1: diagnosis, and neuromuscular, rehabilitation, endocrine, and gastrointestinal and nutritional management. Lancet Neurol. 2018;17(3):251-267. https://doi.org/10.1016/S1474-4422(18)30024-3


5. Birnkrant DJ, Bushby K, Bann CM, et al. Diagnosis and management of Duchenne muscular dystrophy, part 2: respiratory, cardiac, bone health, and orthopaedic management. Lancet Neurol. 2018;17(4):347-361. https://doi.org/10.1016/S1474-4422(18)30025-5


6. Komaki H. Duchenne muscular dystrophy: Evolving therapeutic strategies and multidimensional evaluation approaches. Brain Dev. 2025;47(5):104397. https://doi.org/10.1016/j.braindev.2025.104397

This article is part of the 'Public Education Series' initiative by Exon Publications.

Disclaimer: This article is for general educational purposes only and does not constitute medical advice, diagnosis, or treatment. Consult a qualified healthcare professional about personal health concerns.

Note on External Links: External links were checked and accessible when this article was published. Their content and availability may change over time and are outside the control of Exon Publications.