A vertebral rod includes a first elongated section including a first material having a first modulus of elasticity and a second elongated section including a second material having a second modulus of elasticity. A first intermediate section is disposed between the first section and the second section, and includes a third material having a third modulus of elasticity. The intermediate section has an arcuate inner surface that defines a cavity and an open end. The first modulus and the second modulus are each greater than the third modulus such that the first and second sections provide a reinforced configuration of the vertebral rod and the intermediate section has a relatively flexible configuration.
