Progressive muscle weakness is the main feature of muscular dystrophy. Each separate form of muscular dystrophy varies a bit in terms of the age at which the signs and symptoms usually begin and the sequence in which different muscle groups are affected.

Duchenne muscular dystrophy

About half of all muscular dystrophy cases are the Duchenne variety, which most commonly occurs in boys. Signs and symptoms typically first surface when the child begins to walk and may include:

  • Frequent falls
  • Difficulty getting up from a lying or sitting position
  • Trouble running and jumping
  • Waddling gait
  • Large calf muscles
  • Learning disabilities

Becker muscular dystrophy

This variety has signs and symptoms similar to Duchenne muscular dystrophy, but they typically are milder and progress more slowly. Symptom onset is generally in the teens but may not occur until the mid-20s or even later.

Other types of muscular dystrophy

Certain other types of muscular dystrophy are defined by a specific feature or the location of the body where symptoms first begin. Examples include:

  • Myotonic. Also known as Steinert's disease, this form of muscular dystrophy also features an inability to relax muscles at will. It most often begins in early adulthood. Muscles of the face are usually the first to be affected.
  • Limb-girdle. The hip and shoulder muscles are usually the first affected in this type of muscular dystrophy. In some cases, it becomes difficult to lift the front part of the foot, so frequent tripping may occur. Signs and symptoms may begin from early childhood to adulthood.
  • Congenital. This category of muscular dystrophy is apparent at birth or becomes evident before age 2. Some forms progress slowly and cause only mild disability, while others progress rapidly and cause severe impairment.
  • Fascioscapulohumeral (FSHD). One of the most striking signs of this variety of muscular dystrophy is that the shoulder blades might stick out like wings when the person raises his or her arms. Onset usually occurs in teens or young adults.
  • Oculopharyngeal. The first sign of this type of muscular dystrophy is usually drooping of the eyelids. Weakness of the muscles of the eye, face and throat often results in swallowing difficulties. Signs and symptoms first appear in adulthood, usually in a person's 40s or 50s.

When to see a doctor

Seek medical advice if you notice signs of muscle weakness — such as increased clumsiness and falling — in yourself or your child.

Jan. 18, 2012