forearm deformities
Last reviewed 01/2018
The forearm deformities in ulnar dysplasia are primarily hypoplasia of the ulna with either complete or partial absence. Hypoplasia is more common than partial absence which in turn is more common than complete absence. Consequently, the forearm is shorter than normal. The radius may be affected in the more severe forms with bowing, a slanted distal end and possible fusion to the humerus. The radial head can be dislocated. Alternatively, in more mild forms, the radius may be normal.
There may be corresponding abnormalities of the forearm muscles, tendons, nerves and vascular supply.