Subclavian artery aneurysm secondary to a cervical supernumerary rib in a child.

A case of subclavian artery aneurysm secondary to a cervical supernumerary rib is reported in a 9-year-old boy. Such a complication in a cervical rib has never been reported in so young a child. The risk of inserting inextensible prosthetic material in a growing child led to regular supervision instead of an early surgical cure.