Inserting anterior and posterior spinal prostheses

1. Spinal apparatus comprising:

a reference structure spatially fixed relative to a plurality of pedicle screws that are adapted to be mounted in adjacent vertebrae of a patient;

a device connected to said reference structure which is adapted to install an anterior spinal prosthesis, wherein said reference structure defines a spatial relationship between said anterior spinal prosthesis and a posterior spinal prosthesis attached to said pedicle screws; and

a positioning adapter attached to a plurality of pedicle screws, said positioning adapter comprising a pair of connecting devices, each connecting device comprising a pair of arms that extend outwards corresponding to a spacing of a pair of pedicle screws mounted on a particular vertebra, said arms being attached to that pair of pedicle screws, wherein said connecting devices are formed with said reference structure;

wherein said device comprises a disc implant holder adapted to hold an anterior spinal prosthesis, and further comprising a connecting element adapted to fix said disc implant holder to said positioning adapter with respect to said reference structure.

2. The spinal apparatus according to claim 1 , wherein said positioning adapter is attached to a distraction device adapted to distract two vertebrae to which the pedicle screws are attached.

3. The spinal apparatus according to claim 1 , wherein said disc implant holder comprises a handle from which extends a proximal shaft, and a distal shaft pivotally attached to said proximal shaft at a pivot, wherein said distal shaft comprises a pair of clamping jaws adapted to hold the anterior spinal prosthesis.

4. The spinal apparatus according to claim 1 , wherein said connecting element comprises a tubular portion through which a portion of said disc implant holder passes and a flange portion that is fixedly attachable to said positioning adapter at said reference structure.

5. The spinal apparatus according to claim 4 , wherein a portion of said disc implant holder passes through said tubular portion anteriorly towards said anterior spinal prosthesis and another portion of said disc implant holder extends posteriorly through said tubular portion.