From published cases of humeroradial synostoses three entities can be delineated: AD ankylosis of the elbow as a part of a systemic disorder causing multiple synostoses (symphalangism), AR humeroradial synostosis with dysgenesis of the ulna (and fibula?) but without oligodactyly as part of a syndromal disorder, non-germinal uni- or bilateral humeroradial synostosis as part of ulnar malformation and oligodactyly. Three new observations are considered examples of the latter entity.