Cervical Rib

Weston (1956) found cervical ribs or enlarged transverse processes in 14 of 20 members of a family. The anomaly was particularly striking among the offspring of 2 affected parents, raising the question of homozygosity. Schapera (1987) observed 9 affected persons in 5 sibships of 3 generations (and, by implication, a fourth) of a South African family. There was no instance of male-to-male transmission. Of the 9 affected persons, 5 were males. The expression varied from unilateral enlargement of the transverse processes of C7 to bilateral complete cervical ribs. The number of vertebrae was normal in all the affected and unaffected members of the family. Two family members had experienced severe neurovascular complications. Schapera (1987) suggested that this represents autosomal dominant inheritance, especially when the full range of expression is taken into account.