Duchenne muscular dystrophy

The muscular dystrophies are a group of inherited conditions in which there is breakdown of muscle fibres, leading to gradually increasing weakness. The following information is about the most common form, Duchenne muscular dystrophy.

What is Duchenne muscular dystrophy?

Duchenne muscular dystrophy is characterised by progressive muscle wasting and weakness. It begins with changes in the muscle due to breakdown of muscle fibres leading to gradually increasing muscle weakness. 99% of children diagnosed with Duchenne muscular dystrophy are boys.

More than one boy in the family may be affected and female siblings may be ‘carriers’ of the condition. This means that while they do not ‘show’ the condition, they carry the condition in their genes and may pass it on to their children. Genetic counselling of families is very important to learn about the inheritance pattern in their family.

 

The course of Duchenne muscular dystrophy

The course of Duchenne muscular dystrophy generally is:

  • lateness in learning to walk
  • in toddlers, enlarged calf muscles may be apparent
  • at about three to six years of age, they may appear to be clumsy in their movements, and start to have problems with climbing stairs, getting up from the floor, difficulty with running and frequent falls
  • by school age the child usually has developed a ‘waddling’ walking pattern and is walking on their toes due to increasing weakness of the leg muscles
  • unsteadiness and frequent falls are common at this age, and increasing weakness of arm and trunk muscles too
  • loss of ability to walk and require a wheelchair may occur between the ages of 7-12 years old
  • some people may have some degree of a learning disability
  • weakness of breathing muscles and difficulty with coughing tends to occur more so once they have stopped walking. This can lead greater risk of the child developing chest infections
  • curving of the spine (scoliosis) can develop due to increasing weakness of the muscles that support the spine and may require surgery to correct this
  • weakness of the heart muscle requiring a cardiac evaluation by a specialist in early childhood following diagnosis and regular checks

 

Treatment

While there is no definitive treatment for DMD, there is a lot of research currently happening exploring the effects of new drugs. At the present time, the only drug treatment for DMD with sufficient evidence to support its use, is steroid treatment. This treatment has been found to slow the progress of the muscle weakness, and keep the child walking for a longer period. Side effects of steroid use vary and may be a problem, so needs to be managed well by the prescribing doctor.

Physiotherapy and occupational therapy is important from the early stages. Maintaining good range of movement and symmetry is important. Timely provision of splints, assistive devices and wheelchair and seating is vital in supporting independence and participation in their lives. It is important that the young person has good access to medical management in the latter phase of the disease as respiratory and cardiac issues become more evident.

 

Other helpful links

The Diagnosis and Management of Duchenne Muscular Dystrophy
An online guide for families summarises the results of an international consensus on the medical care of Duchenne muscular dystrophy.

Muscular Dystrophy Association – South Australia
Provides a range of information and support and recreational services for children with muscular dystrophy and other neuromuscular disorders, their families and their carer/support provider.

Save our Sons
Provides news and research on Duchenne muscular dystrophy.

Muscular Dystrophy Association – United States of America
Provides information about the muscular dystrophies, research and support services for people with the condition as well as ways people can support the organisation’s fundraising efforts.

Muscular Dystrophy Australia
Provides on-line chat and videoconferencing facilities as well as information about this condition and relevant services.