Open chambered spacers, implanting tools and methods are provided. The spacers 500′ include a body 505′ having a wall 506′ which defines a chamber 530′ and an opening 531′ in communication with the chamber 530′. In one embodiment the wall 506′ includes a pair of arms 520′, 521′ facing...http://www.google.co.uk/patents/US7993406?utm_source=gb-gplus-sharePatent US7993406 - Open intervertebral spacer
