If you’re a caregiver for someone with Duchenne muscular dystrophy (DMD), you have likely noticed early signs in your child that led to their diagnosis. Although DMD is caused by gene mutations present at birth, major symptoms don’t typically appear for a few years. Signs of DMD typically become noticeable between ages 3 and 6 and worsen over time.

Many factors, including other genetic disorders, medical conditions, and environmental influences, can cause a child to grow and develop more slowly than expected. Additionally, even though DMD can be caused by genetic factors, some people with the condition don’t have a family history of it. This means that when a child displays their first symptoms, it’s often not immediately apparent that DMD is the cause.

For caregivers whose child hasn’t yet been diagnosed, keeping an eye out for these seven common signs of Duchenne muscular dystrophy and discussing them with your child’s pediatrician may help lead to an earlier diagnosis.

1. Developmental Delays

Health care providers use developmental milestones to determine whether a child is growing and developing as expected. These milestones describe when, on average, children tend to start displaying certain motor skills, thinking abilities, or behaviors.

One of the first signs of DMD is if your child misses developmental milestones. In a study of young males with DMD, researchers found that most started missing milestones by the time they were 2 or 3 months old, and they tended to miss more as they got older. For example:

• About 22 percent of males couldn’t lift their heads while lying down by the time they were 3 months old.
• Just over half were unable to walk by themselves by the time they reached 18.5 months.
• About 4 out of 10 were unable to say two-word sentences at 25 months.

Missing milestones isn’t always a sign of a serious condition like DMD. Children develop at different rates, and many healthy children hit milestones later than expected. However, if you regularly notice signs that your child isn’t developing at the same rate as their peers, it may be time for a conversation with their pediatrician.

2. Weakened Muscles

One of the main symptoms of DMD is progressive muscle weakness. DMD affects the production of dystrophin, a protein needed for the skeletal muscles. Decreases in muscle strength often first affect your child’s hips and legs but may also affect the arms or neck.

A young child may not be able to hold up their head as well as expected. They may have difficulty crawling, walking, or going upstairs.

As your child gets older, you may notice that they can’t move around or play in the same way as other children their age. Your child may also walk unusually — for example, they may walk on their toes, waddle, or arch their back.

3. Gowers’ Sign

Another sign of DMD-related muscle weakness is Gowers’ sign, a maneuver in which a child walks their hands up their legs as they stand up. Mobility and balance issues, such as frequent falls or tripping, may also signal DMD.

These issues develop when muscle fibers aren’t as strong as they need to be. They may also be caused by contractures (stiffened or shortened muscles) or scoliosis (a curved spine).

Muscle problems may change the appearance of muscles. Many kids with DMD have enlarged calves due to the presence of other tissues that replaced the muscle, which makes their lower legs look wider or more muscular than expected. However, muscles in the abdomen, shoulders, pelvis, and upper legs may atrophy (become smaller).

4. Behavior Problems

Another sign of DMD includes problems with behavior. Symptoms of behavioral issues vary from person to person. Some children with DMD are reliant on routine and find change extremely stressful.

It’s common to experience difficulty communicating, as well as social difficulties, which can lead to trouble making friends or playing. Therefore, children with DMD may frequently spend time alone and struggle with irritability, anger, or negative thoughts.

5. Learning Problems

About 1 in 3 kids with DMD have signs of cognitive impairment (difficulties with thinking or memory abilities) that can affect their quality of life. Children with DMD are more likely to be diagnosed with learning disabilities, attention-deficit/hyperactivity disorder (ADHD), or autism.

Symptoms of learning problems may include:

• Problems focusing
• Poor memory
• Poor academic performance

If your child is suspected to have DMD, interventions should begin as early as possible. Caregivers, doctors, psychologists, and teachers should work together to create the best plan for each child with DMD.

6. Falls and Balance Issues

As muscles get weaker over time, many children with DMD have trouble balancing. This makes it more likely that they will trip or fall. These balance issues are often noticeable in young children who are just starting to walk, although this may be hard to differentiate from the way any toddler might fall. Frequent falls are caused by weakened muscles in the legs and pelvis, which are important for maintaining stability. If you find that your child is falling frequently or seems clumsier than other kids their age, it may be helpful to bring it up with their doctor.

7. Abnormal Posture

With DMD, weakness of certain muscles can lead to changes in body positioning over time. Examples of this include abnormal curvature of the spine (such as scoliosis), loss of muscle in the upper legs, and stiffness of joints into abnormal positions (contractures). Children with DMD may stick out their bellies and pull their shoulders back to compensate for weak muscles and keep their balance.

Intensive physical therapy that focuses on strengthening and mobility can help delay the need for leg braces and wheelchairs. By age 12, most children with DMD start to use a wheelchair to aid in their mobility.

Talk With Others Who Understand

On myMDteam, the site for caregivers and people living with muscular dystrophy, members come together to gain a new understanding of muscular dystrophy and share their stories with others who understand life with the condition.

What were the first signs or symptoms that you noticed of Duchenne muscular dystrophy? Have these symptoms changed over time? Share your experiences in the comments below or by posting on your Activities page.