[Connection between deviated axis and impaired function after fractures of the forearm (author's transl)].

Based on follow-up studies of forearm fractures in children the connection between malunion and limitation of forearm rotation has been examined. This limitation of forearm rotation is often caused by deviations of the ulnar and radial shaft in the same direction which have not been corrected by growth. With the aid of geometric drawings it is demonstrated that palmar deviations of bones lead to limited supination whereas dorsal deviations must cause reduced pronation. This limitation increases in proportion to the angle of deviation and proximity to shaft middle.