is usually characterized by malformed wrists and wrist bones and short stature and is often associated with Léri-Weill dyschondrosteosis
. It has only been recognized within the past hundred years, and occurs due to a genetically recessive gene
It is a congenital subluxation
of the ulna
's lower end, due to malformation of the bones. Sometimes, minor abnormalities of other bone structures, often caused by disease or injury, such as a fracture of the lower end of the radius
with upward displacement of the lower fragment. The deformity varies in degree from a slight protrusion of the lower end of the ulna, to complete dislocation of the inferior radio-ulnar joint
with marked radial deviation of the hand. Severe deformities are associated with congenital absence or hypoplasia
of the radius.
The operation consists of excision of the lower end of the ulna; in severe cases of marked radial deviation, it may be necessary also to fuse the radius to the carpus
in order to gain correction.
It is named for Otto Wilhelm Madelung