Driver assembly for simultaneous axial delivery of spinal implants

Tools for use in the deployment of spinal implant assemblies such as spinal motion preservation assemblies adapted for use in a spinal motion segment are disclosed including the process for delivering and assembling the spinal motion preservation assemblies in the spinal motion segment via an axial channel created with a trans-sacral approach. The tools allow the deployment of a pair of spinal implant components that are not rigidly connected to one another to be driven into adjacent vertebral bodies. The tools further allow for distraction via either dissimilar thread pitch or by axially advancing a distraction tool based on a threaded engagement with a proximal component in a proximal vertebral body to impose an distraction between that vertebral body and an adjacent distal vertebral body. The tools also allow for the provision of flowable biomaterials such as prosthetic nucleus material. Delivery of flowable biomaterials can be performed while the vertebrae are being held apart by a distraction tool.