Myotonic muscular dystrophy

Myotonic dystrophy is a common form of muscular dystrophy, characterized by muscle wasting, weakness and myotonia (tightness and stiffness) in the face, neck, hands and lower legs. This genetic disorder is of two types: type 1 and type 2, depending on the gene that is affected. It is a condition that worsens over time and can progress to disability.

Symptoms of myotonic dystrophy usually develop when you are in your twenties or thirties and include:

• Difficulty in relaxing muscles after they have been used: For example, you will not be able to release your grip in a handshake or on a doorknob
• Cardiac conduction defects: irregular heartbeats
• Cataracts
• Hormonal problems in males: balding and infertility
• Breathing problems, muscle weakness and developmental delays including mental retardation

Your doctor performs a physical examination to identify the typical pattern of muscle wasting and weakness, and the presence of myotonia. An electromyography test to examine the electrical activity of the muscles and a genetic test are ordered to confirm the diagnosis.

There is no specific treatment for myotonic dystrophy. Disease management involves controlling symptoms and improving the patients’ quality of life. As weakness advances, ankle supports and leg braces are prescribed. Myotonia can be reduced with medications. Heart problems and cataracts can be accordingly treated.