Abstract: An endplate for an intervertebral prosthesis includes a generally planar base plate, a first elevated region, or dome, within the base plate periphery, and a second elevated region, or dome, within the boundary of the first elevated region. The antero-posterior and side-to-side (medial-lateral) dimensions of the first elevated region are made to be unequal in order to provide resistance to torsional stresses, and the laterally opposite sidewalls of the first elevated region are defined by arcs that terminate in sagittal planes of the endplate, and are symmetrical with respect to a coronal plane of the endplate. A bone rasp and a groove cutter for use in implanting the prosthesis are also provided.

Abstract: An endplate for an intervertebral prosthesis includes an inner domed region and a peripheral rim wherein the inner domed region has a non-circular plan and has an area that is at least 50% of the area of the endplate. A surgical instrument for milling a recess in a vertebral endplate includes a cutting tool having a drive shaft with a positioning collar, a guard frame, and a pair of guide plates attached to the guard frame and spaced to confine the positioning collar and having guide slots for the drive shaft.

Abstract: An endplate for an intervertebral disc prosthesis includes: a baseplate, sized and configured to fit within at least a portion of an intervertebral space, and an anterior portion having an outer vertebra-contacting surface extending outwardly from the baseplate at an acute angle with respect to an axis of the baseplate, and being provided with an opening configured to receive a fastener.

Abstract: An endplate for an intervertebral prosthesis includes a generally planar base plate, a first elevated region, or dome, within the base plate periphery, and a second elevated region, or dome, within the boundary of the first elevated region. The antero-posterior and side-to-side (medial-lateral) dimensions of the first elevated region are made to be unequal in order to provide resistance to torsional stresses, and the laterally opposite sidewalls of the first elevated region are defined by arcs that terminate in sagittal planes of the endplate, and are symmetrical with respect to a coronal plane of the endplate. A bone rasp and a groove cutter for use in implanting the prosthesis are also provided.

Abstract: An endplate for an intervertebral prosthesis includes a generally planar base plate, a first elevated region, or dome, within the base plate periphery, and a second elevated region, or dome, within the boundary of the first elevated region. The antero-posterior and side-to-side (medial-lateral) dimensions of the first elevated region are made to be unequal in order to provide resistance to torsional stresses, and the laterally opposite sidewalls of the first elevated region are defined by arcs that terminate in sagittal planes of the endplate, and are symmetrical with respect to a coronal plane of the endplate. A bone rasp and a groove cutter for use in implanting the prosthesis are also provided.

Abstract: An endplate for an intervertebral prosthesis includes an inner domed region and a peripheral rim wherein the inner domed region has a non-circular plan and has an area that is at least 50% of the area of the endplate. A surgical instrument for milling a recess in a vertebral endplate includes a cutting tool having a drive shaft with a positioning collar, a guard frame, and a pair of guide plates attached to the guard frame and spaced to confine the positioning collar and having guide slots for the drive shaft.

Abstract: A surgical implant, especially an artificial intervertebral disc, includes a rigid substrate (513) having a porous attachment structure (512) that covers a portion of the substrate and an elastomeric body (510) that is fastened to the substrate by impregnating the porous attachment structure. The porous attachment structure has a net porosity greater than 21.5%. The porous attachment structure may be, for example, a perforated plate or a screen spaced from a substrate surface, or a layer of trabecular metal or an open-cellular material.

Abstract: An endplate for an intervertebral prosthesis includes an inner domed region (330) and a peripheral rim (332) wherein the inner domed region has a non-circular plan and has an area that is at least 50% of the area of the endplate. A surgical instrument for milling a recess in a vertebral endplate includes a cutting tool having a drive shaft with a positioning collar, a guard frame, and a pair of guide plates attached to the guard frame and space to confine the positioning collar and having guide slots for the drive shaft.

Abstract: The present invention provides an orthopedic device assembly comprising a first assembly element, a second assembly element, and a retaining mechanism. The first assembly element has a recess that receives the second assembly element, and the retaining mechanism holds the second element in an assembled state with the first assembly element. The retaining mechanism includes a retaining member with an angular cross-section defined by a base portion and a lateral flange portion projecting from the base portion. The retaining member is inserted through an aperture of the first assembly element into a groove in a wall of the recess of the first assembly element, with the flange portion projecting laterally of the groove and overhanging a shoulder portion of the second assembly element so as to retain the second assembly element in the assembled state with the first assembly element.

Abstract: The present invention provides an orthopedic device assembly comprising a first assembly element, a second assembly element, and a retaining mechanism. The first assembly element has a recess that receives the second assembly element, and the retaining mechanism holds the second element in an assembled state with the first assembly element. The retaining mechanism includes a retaining member with an angular cross-section defined by a base portion and a lateral flange portion projecting from the base portion. The retaining member is inserted through an aperture of the first assembly element into a groove in a wall of the recess of the first assembly element, with the flange portion projecting laterally of the groove and overhanging a shoulder portion of the second assembly element so as to retain the second assembly element in the assembled state with the first assembly element.

Abstract: The present invention provides an orthopedic device assembly comprising a first assembly element, a second assembly element, and a retaining mechanism. The first assembly element has a recess that receives the second assembly element, and the retaining mechanism holds the second element in an assembled state with the first assembly element. The retaining mechanism includes a retaining member with an angular cross-section defined by a base portion and a lateral flange portion projecting from the base portion. The retaining member is inserted through an aperture of the first assembly element into a groove in a wall of the recess of the first assembly element, with the flange portion projecting laterally of the groove and overhanging a shoulder portion of the second assembly element so as to retain the second assembly element in the assembled state with the first assembly element.

Abstract: In an intervertebral disc prostheses having a pair of rigid endplates and an elastomeric core structure between the endplates. The core structure is designed to provide desired functional characteristics of the prosthesis.

Abstract: An endplate for an intervertebral prosthesis includes an inner domed region (330) and a peripheral rim (332) wherein the inner domed region has a non-circular plan and has an area that is at least 50% of the area of the endplate. A surgical instrument for milling a recess in a vertebral endplate includes a cutting tool having a drive shaft with a positioning collar, a guard frame, and a pair of guide plates attached to the guard frame and space to confine the positioning collar and having guide slots for the drive shaft.

Abstract: The present invention provides an orthopedic device assembly comprising a first assembly element, a second assembly element, and a retaining mechanism. The first assembly element has a recess that receives the second assembly element, and the retaining mechanism holds the second element in an assembled state with the first assembly element. The retaining mechanism includes a retaining member with an angular cross-section defined by a base portion and a lateral flange portion projecting from the base portion. The retaining member is inserted through an aperture of the first assembly element into a groove in a wall of the recess of the first assembly element, with the flange portion projecting laterally of the groove and overhanging a shoulder portion of the second assembly element so as to retain the second assembly element in the assembled state with the first assembly element.

Abstract: An intervertebral disc prosthesis includes upper and lower rigid endplates and an elastomeric core structure located between the endplates and attached thereto, wherein the elastomeric core structure has a centroid positioned posterior to a centroid of at least one of the endplates.

Abstract: A surgical implant, especially an artificial intervertebral disc, includes a rigid substrate (513) having a porous attachment structure (512) that covers a portion of the substrate and an elastomeric body (510) that is fastened to the substrate by impregnating the porous attachment structure. The porous attachment structure has a net porosity greater than 21.5%. The porous attachment structure may be, for example, a perforated plate or a screen spaced from a substrate surface, or a layer of trabecular metal or an open-cellular material.

Abstract: An endplate for an intervertebral prosthesis prosthesis endplate of the invention includes: a generally planar base plate, a first elevated region, or dome, within the base plate periphery, and a second elevated region, or dome, within the boundary of the first elevated region. The antero-posterior and side-to-side (medial-lateral) dimensions of the first elevated region are made to be unequal in order to provide resistance to torsional stresses, and the laterally opposite sidewalls of the first elevated region are defined by arcs that terminate in sagittal planes of the endplate, and are symmetrical with respect to a coronal plane of the endplate. A bone rasp for preparing a surgical site for implantation of the prosthesis has a rasp head having a pivot point and rasp teeth arranged to produce a recess or seat of predetermined shape.

Abstract: In an intervertebral disc prostheses having a pair of rigid endplates and an elastomeric core structure between the endplates. The core structure is designed to provide desired functional characteristics of the prosthesis.

Abstract: A suite of surgical tools for use in implantation of an intervertebral disc prosthesis is provided. The surgical tools include an external alignment frame (EAF), an annulus incision guide (AIG), a depth gauge, a positioning/alignment block, a disc space distractor, an endplate drill guide (EDG), and a vertebral endplate cutter (VEC), any or all of which can be used by a surgeon in a procedure for preparing an implantation site by excising all or part of a degenerated intervertebral disc and implanting an intervertebral disc prosthesis in the site so prepared.

Abstract: An food holder attachable to the outside of the food, such as an ice cream cone, for capturing liquid, the liquid be captured by an absorbent material and in a plurality of channels and interconnections for maximizing the surface of the absorbent material, the channels having openings to allow the liquid to enter via gravity, but small enough that upon momentary tilting of the food the liquid will not spill out of the holder.