CPC A61F 2/30771 (2013.01) [A61F 2/389 (2013.01); A61F 2/3859 (2013.01); A61F 2/4081 (2013.01); A61F 2/4202 (2013.01); A61F 2/4261 (2013.01); A61F 2/442 (2013.01); A61L 27/06 (2013.01); A61L 27/18 (2013.01); A61F 2/2803 (2013.01); A61F 2002/30069 (2013.01); A61F 2002/3093 (2013.01); A61F 2002/30224 (2013.01); A61F 2002/30326 (2013.01); A61F 2002/30383 (2013.01); A61F 2002/30896 (2013.01); A61F 2002/3863 (2013.01); A61F 2002/4205 (2013.01); A61F 2002/4207 (2013.01); A61F 2310/00017 (2013.01); A61F 2310/00023 (2013.01); A61F 2310/00029 (2013.01); A61F 2310/00293 (2013.01); A61F 2310/00359 (2013.01); A61L 2430/02 (2013.01); A61L 2430/38 (2013.01)] | 13 Claims |
1. A tibial implant for knee, the tibial implant comprising:
(a) a bulk implant;
(b) a planar face defining an exterior bone-engaging surface of the bulk implant, the exterior bone-engaging surface sized and configured to contact a resected surface of a proximal tibia;
(c) pillars for contacting a hard tissue, the pillars being distributed on the exterior bone-engaging surface, across an area of at least 30 mm2, and extending perpendicularly from the planar face, and each pillar being integral to the bulk implant, having a distal end, having a transverse area of (100×100) μm2to (10,000 ×10,000) μm2, and having a height of 100 μm to 10,000 μm;
(d) slots to be occupied by the hard tissue, the slots being defined by the pillars and each slot having a width of 100 μm to 10,000 μm as measured along the shortest distance between adjacent pillars; and
(e) at least one support member for contacting the hard tissue, the at least one support member being positioned on the exterior bone-engaging surface among the pillars, extending distally from the exterior bone-engaging surface, having a transverse area greater than the transverse area of any of the pillars, and having a height greater than the height of any of the pillars;
wherein the tibial implant has a Young's modulus of elasticity of at least 3 GPa, and has a ratio of (i) the sum of the volumes of the slots to (ii) the sum of the volumes of the pillars and the volumes of the slots of 0.40:1 to 0.90:1;
wherein:
one or more pillars have dimensions that differ from those of other pillars, such that the transverse areas and/or heights, and thus volumes, of the one or more pillars differ from those of the other pillars; and
the one or more pillars are distributed peripherally with respect to the exterior bone-engaging surface and are intended for insertion into cortical bone, and the other pillars are distributed centrally with respect to the exterior bone-engaging surface and are intended for insertion into cancellous bone; and
wherein the pillars are non-porous.
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