Patent ID: 7115132

Claim:
An instrumentation set for evaluating an intervertebral space, the set comprising: a plurality of trial artificial intervertebral discs, each of which approximates at least a size and a shape of a corresponding one of a plurality of artificial intervertebral discs, one of which plurality of artificial intervertebral discs is to be implanted into the intervertebral space, each of the trials including spaced apart baseplates and a perimetrical groove that establishes a trunk between the baseplates such that the baseplates extend as flanges from either end of the trunk; and a trial artificial intervertebral disc holder suitable for holding any of the trials, the trial holder including a shaft, a sleeve, and a selectively openable and closeable holding enclosure defined by opposing extents at a distal end of the shaft, into which holding enclosure any of the trials is capturable, each of the extents being thinner than a width of the perimetrical groove such that they fit into the perimetrical groove to engage the trunk, the shaft having a portion proximal to the extents that is thicker than the width of the perimetrical groove such that the proximal portion is prevented from fitting into the perimetrical groove; wherein each of the trials further includes opposing recesses adjacent and communicating with the perimetrical groove, one being formed in one of the baseplates and another being formed in the other of the baseplates opposite the one recess, that define a volume dimensioned to accommodate a longitudinal portion of the proximal portion; and wherein when the trial is engaged by the trial holder so that the extents are fitted within the perimetrical groove to engage the trunk between them, the volume defined by the opposing recesses accommodates the longitudinal portion of the proximal portion such that rotation of the trial about an axis perpendicular to the longitudinal axis of the shaft is limited by interference between the longitudinal portion and the opposing recesses.