Muscular Dystrophy Symptoms

Muscular Dystrophy Symptoms That Should Not Be Ignored

Progressive weakness or new problems with movement, swallowing, breathing, or heart function need medical assessment. These symptoms may indicate increasing muscle involvement or complications associated with certain types of muscular dystrophy.

The table below lists muscular dystrophy symptoms that should not be ignored:

Muscular dystrophy is not the only condition that can cause these symptoms. Other muscle and nerve disorders can produce similar problems, so a medical assessment is needed to identify the cause.

Why Do Muscular Dystrophy Symptoms Occur?

Muscular dystrophy occur because genetic changes interfere with proteins that muscle cells need to remain healthy and function normally. It causes the muscles to weaken over time.

Different gene changes are responsible for different types of muscular dystrophy. For example, Duchenne and Becker muscular dystrophies are caused by mutations in the DMD gene, which encodes dystrophin. This protein helps protect muscle fibres during normal movement. When dystrophin is absent or does not work properly, muscle fibres become progressively damaged and weaker.

As muscle weakness progresses, activities such as walking, running, climbing stairs, lifting objects or getting up from the floor can become more difficult. Some forms also affect the heart, breathing muscles or muscles involved in swallowing, leading to additional symptoms.

Muscular Dystrophy Symptoms That Require Immediate Medical Attention

Most muscular dystrophy symptoms develop gradually. However, complications affecting breathing, swallowing or the heart can sometimes require emergency treatment.

Seek immediate medical attention for:

• Severe or rapidly worsening difficulty breathing

• Blue or grey lips or skin with breathing difficulty

• Active choking with difficulty breathing

• Severe breathing problems during a chest infection

• Sudden loss of consciousness

• Severe chest pain with breathlessness or fainting

• A sustained abnormal heartbeat with dizziness or fainting

• Severe swallowing difficulty accompanied by repeated choking or breathing problems

• Extreme drowsiness or difficulty staying awake with breathing problems

Symptoms of Muscular Dystrophy Based on Type

Various types of muscular dystrophy target distinct muscle groups and can emerge at any age. This can produce recognisable symptom patterns, although symptoms alone cannot identify the exact genetic type.

The table below compares the common symptoms of major types of muscular dystrophy:

Symptoms of Muscular Dystrophy in Men

Muscular dystrophy symptoms in men depend on the specific genetic type. In particular, Duchenne and Becker muscular dystrophies primarily affect males because they are X-linked genetic conditions, while several other forms can affect both sexes.

Symptoms of muscular dystrophy in men may include:

• Developing progressive muscle weakness, often beginning in the hips, thighs or shoulders

• Experiencing difficulty running, jumping or climbing stairs

• Falling frequently or having difficulty getting up from the floor

• Walking on the toes or developing an unusual walking pattern

• Developing enlarged calf muscles

• Experiencing increasing difficulty walking as muscle weakness progresses

• Developing joint stiffness or contractures

• Experiencing heart or breathing problems in some forms

Symptoms of Muscular Dystrophy in Women

Women carrying a DMD gene change may have no noticeable symptoms, but some can develop:

• Mild muscle weakness

• Muscle cramps

• Difficulty with physical activity

• Unusual muscle tiredness

• Shortness of breath related to heart involvement

• Palpitations or other symptoms associated with cardiomyopathy

Female carriers have an increased risk of cardiomyopathy, even when skeletal muscle symptoms are mild or absent. Because of this risk, routine cardiac screening (such as echocardiograms or cardiac MRIs) is medically recommended for all confirmed carriers.

In rare cases (such as skewed X-inactivation), females can also develop severe, full-spectrum muscular dystrophy symptoms similar to males.

Symptoms of Muscular Dystrophy in Children

Several forms of muscular dystrophy begin during infancy or childhood. Early symptoms may appear as delayed motor development or increasing difficulty with physical activities expected for the child's age.

Common signs of muscular dystrophy in children include:

• Delayed sitting, standing or walking

• Frequent falls

• Difficulty running or jumping

• Difficulty climbing stairs

• Difficulty getting up from the floor

• Waddling while walking

• Walking on the toes in some children

• Enlarged-looking calf muscles in Duchenne muscular dystrophy

• Difficulty keeping up with other children during physical activities

• Gradually worsening muscle weakness

Duchenne muscular dystrophy usually becomes noticeable before the age of five, while Becker muscular dystrophy often starts later and progresses more slowly.

Frequent falls or delayed movement do not automatically mean that a child has muscular dystrophy. Persistent motor difficulties should be medically assessed because several developmental, muscle and nerve conditions can cause similar symptoms.

Can You Have Muscular Dystrophy Without Symptoms?

Some forms of muscular dystrophy may be present for a period before noticeable muscle weakness develops. Certain types begin during infancy or childhood, while others do not become apparent until adolescence or adulthood.

A person can also carry a genetic change associated with muscular dystrophy without developing obvious symptoms. For example, many women carrying a DMD gene change have no skeletal muscle symptoms, although some develop mild muscle weakness, cramps or heart problems.

Being an asymptomatic genetic carrier (who inherits a gene variant without having the disease) is distinct from the pre-clinical phase of muscular dystrophy, where elevated muscle enzymes and microscopic tissue damage occur before outward physical symptoms appear. Once significant muscle weakness develops, changes in movement or physical ability usually become noticeable.

When Can Muscular Dystrophy Symptoms Become Life-Threatening?

Muscular dystrophy can become life-threatening when weakness significantly affects breathing or swallowing or when a particular type affects the heart. The overall risk varies significantly between different types of muscular dystrophy and depends on factors such as:

How are Muscular Dystrophy Symptoms Diagnosed?

Muscular dystrophy is assessed using the pattern of muscle weakness, the age at symptom onset, physical examination, and family history. Further tests help determine whether a muscle disorder is present and identify the specific form of muscular dystrophy.

The table below summarises the main tests and assessments used when muscular dystrophy is suspected:

Targeted DNA genetic testing is the definitive primary method used to diagnose most muscular dystrophies, including Myotonic Dystrophy, while tests like blood work, EMG, MRI, or muscle biopsy are reserved for complex cases where genetic findings are inconclusive.