Impaired pronation-supination of the forearm: an inherited condition.

Davenport, Taylor, and Nelson (1924) have reported several instances of familial radio-ulnar synostoses with variable degrees of reduction in pronation and supination. Their cases fall into three general types: (1) radius without a head; (2) radial head displaced backwards; and (3) radial head more or less normal but radial shaft strongly curved. Cockshott and Omololu (1958) reported a father and daughter with bilateral posterior dislocation of the radial head, with limitation of flexion and extension of the elbow but with normal pronation and supination. Gunn and Pillay (1964) reported a mother-daughter pair with the same deformity and limited pronation-supination.