Ortho Oracle - orthopaedic operative atlas
Home » Muscles Tendons » Myotonic Muscular Dystrophy

Myotonic Muscular Dystrophy

- Discussion:
    - myotonic muscular dystrophy is an autosomal dominant disease;
    - there is widespread involvement of organ systems, which includes weakness and wasting of the muscles, cataracts of the posterior lens,
             endocrine abnormalities, cardiac conduction defects, premature frontal balding in males, and, frequently, nonprogressive intellectual 
    - muscle wasting and weakness are unlike those found in most dystrophies in that they start in the distal parts of the limbs and progress 
    - feature that gives the disease its name is myotonia, the inability of muscle to relax following contraction;
    - myotonia is seen when patient is asked to squeeze his fist hard and then open it quickly;
    - fingers will straighten only gradually;
    - pts are usually able to continue walking for many years, although heavy physical exercise becomes impossible;
    - sudden cardiac dysrhythmias may cause death but are preventable by use of a cardiac pacemaker

Current Concepts Review.  The Diagnosis and Orthopaedic Treatment of Inherited Muscular Diseases of Childhood.

NEJM: Images in Clinical Medicine. Myotonic Dystrophy