muscular dystrophy

Any of a group of inherited chronic muscle disorders marked by weakening and wasting of muscle. Muscle fibres degenerate, to be replaced by fatty tissue, although the nerve supply remains unimpaired. Death occurs in early adult life.

The commonest form, Duchenne muscular dystrophy, strikes boys (1 in 3,000), usually before the age of four. The child develops a waddling gait and an inward curvature (lordosis) of the lumbar spine. The muscles affected by dystrophy and the rate of progress vary. There is no cure, but physical treatments can minimize disability. Death usually occurs before the age of 20.