Muscular Dystrophy

Types of Muscular Dystrophy

Here are some common types of muscular dystrophy:

1. Duchenne Muscular Dystrophy (DMD): This is the most common and severe form, primarily affecting boys. Symptoms usually appear between ages 2 and 5 and include progressive muscle weakness and loss of mobility, often leading to wheelchair dependence in the early teens.

2. Becker Muscular Dystrophy (BMD) is similar to DMD but generally milder and with a later onset. Symptoms typically appear in adolescence or early adulthood, and muscle weakness progresses slowly.

3. Myotonic Dystrophy: This type affects both men and women and can present at any age. Symptoms include muscle stiffness (myotonia), weakness, and other systemic issues such as cardiac problems and cataracts.

4. Limb-Girdle Muscular Dystrophy (LGMD): This group of disorders affects the muscles around the hips and shoulders. Onset can occur in childhood, adolescence, or adulthood, and the severity can vary widely.

5. Facioscapulohumeral Muscular Dystrophy (FSHD): This type primarily affects the muscles of the face, shoulders, and upper arms. Symptoms usually appear in the teenage years or early adulthood and may progress slowly.

6. Congenital Muscular Dystrophy (CMD): Present at birth, CMD encompasses a group of muscular dystrophies characterized by muscle weakness and atrophy. The severity and specific symptoms can vary significantly.

7. Oculopharyngeal Muscular Dystrophy (OPMD): This type primarily affects adults and is characterized by muscle weakness in the eyelids and throat, which can lead to difficulty swallowing and drooping eyelids.

Each type of muscular dystrophy has its unique characteristics, progression, and management strategies, and early diagnosis is crucial for optimizing treatment and care.

What are the causes of Muscular dystrophy?

Muscular dystrophy is caused by mutations in genes responsible for producing proteins that are essential for muscle development and function. These mutations interfere with the normal formation of healthy muscle tissue, leading to muscle degeneration and weakness. The specific cause of muscular dystrophy depends on the type, but here are some common causes:

1. Genetic Mutations: Muscular dystrophy is typically inherited and passed down through families. Mutations in the genes that control muscle proteins, like dystrophin (in Duchenne and Becker muscular dystrophy), lead to the progressive weakening of muscles.

2. X-Linked Recessive Inheritance: Duchenne and Becker muscular dystrophies are caused by mutations in the DMD gene located on the X chromosome. These types mainly affect boys, as males have only one X chromosome, and a mutation can lead to the disease.

3. Autosomal Dominant Inheritance: In some forms of muscular dystrophy, like Facioscapulohumeral Muscular Dystrophy (FSHD), a mutated gene from just one parent is enough to cause the disease.

4. Autosomal Recessive Inheritance: Some types, like Limb-Girdle Muscular Dystrophy (LGMD), are inherited when both parents pass down a copy of the mutated gene, even if neither parent has the disease.

What are the symptoms of muscular dystrophy?

The primary symptom of muscular dystrophy is the gradual weakening of muscles. The onset of signs and symptoms and the muscles affected vary depending on the muscular dystrophy type.

Duchenne Muscular Dystrophy (DMD)

This is the most common type of muscular dystrophy, primarily affecting boys, although girls can be carriers and experience mild symptoms.

Symptoms typically appear in early childhood and may include:

• Frequent falls
• Difficulty getting up from a sitting or lying position
• Challenges with running and jumping
• Waddling walk
• Walking on tiptoes
• Enlarged calf muscles
• Muscle pain and stiffness
• Learning difficulties
• Delayed growth

Becker Muscular Dystrophy (BMD)

Becker muscular dystrophy has similar symptoms to Duchenne, but the progression is slower and less severe. Symptoms usually appear during adolescence but may not manifest until the mid-20s or later.

Other Types of Muscular Dystrophy

• Myotonic Muscular Dystrophy is characterized by difficulty relaxing muscles after contraction. Muscles in the face and neck are usually affected first. Individuals with this form often have long, thin faces, drooping eyelids, and a "swan neck" appearance.
• Facioscapulohumeral Muscular Dystrophy (FSHD): Weakness typically begins in the muscles of the face, hips, and shoulders. People with this condition may experience shoulder blades that stick out like wings when raising their arms. Symptoms usually start during adolescence, though onset can range from childhood to middle age.
• Congenital Muscular Dystrophy: This type affects both boys and girls and becomes noticeable at birth or before age 2. Some forms progress slowly with mild symptoms, while others advance rapidly, leading to significant impairment.
• Limb-Girdle Muscular Dystrophy: This form typically affects the muscles around the hips and shoulders. Individuals may have difficulty lifting the front part of their foot, leading to frequent tripping. Symptoms usually appear in childhood or during adolescence.

When to see a doctor

Consult a doctor if you or your child experience signs of muscle weakness, such as increased clumsiness or frequent falls.