Prosthetic device, method of planning bone removal for implantation of prosthetic device, and robotic system

Abstract

A prosthetic device, method for planning bone removal, and a robotic system for implantation of a prosthetic device in bone are disclosed. The prosthetic device can include a body portion for attachment to a bone, wherein the body portion includes an implantation surface configured to face the bone upon implantation, and a constraint structure. The prosthetic device, method, and robotic system can be configured to cause the constraint structure and bone to interact so as to constrain the prosthetic device in the bone.

1 . A prosthetic device for implantation in bone, comprising:
 a body portion for attachment to a bone, wherein the body portion includes an implantation surface configured to face the bone upon implantation; and   constraint structure comprising at least one of:
 (i) at least one compressive projection projecting from the implantation surface in a lateral direction of the body portion and configured to provide a compressive force between the at least one compressive projection and the bone, 
 (ii) at least one interlock projection projecting from the implantation surface and having an interlock-projection surface configured to receive bone in a space between the interlock-projection surface and a proximal portion of the implantation surface, and 
 (iii) at least one recess in the implantation surface and configured to receive bone to constrain the body portion in at least two translational degrees of freedom, 
   wherein the constraint structure is configured to constrain the prosthetic device in the bone.   
     
     
         2 . The prosthetic device of  claim 1 , wherein the at least one compressive projection is configured to include a bone-engaging surface for engaging the bone and a free surface that does not engage the bone. 
     
     
         3 . The prosthetic device of  claim 1 , comprising at least three compressive projections. 
     
     
         4 . The prosthetic device of  claim 1 , wherein the interlock-projection surface includes a substantially planar portion that projects over and extends at an acute angle relative to the proximal portion of the implantation surface. 
     
     
         5 . The prosthetic device of  claim 1 , wherein the interlock-projection surface includes a substantially arcuate portion that projects over the proximal portion of the implantation surface. 
     
     
         6 . The prosthetic device of  claim 1 , wherein the at least one interlock projection includes an additional interlock-projection surface configured to receive bone in a space between the additional interlock-projection surface and a proximal portion of the implantation surface. 
     
     
         7 . The prosthetic device of  claim 1 , wherein the at least one recess includes an inner surface and a recess surface, wherein the recess surface is disposed between the inner surface and a proximal portion of the implantation surface so as to form a space for receiving bone between the recess surface and the inner surface. 
     
     
         8 . The prosthetic device of  claim 7 , wherein the recess surface includes a substantially planar portion that extends at an obtuse angle relative to the proximal portion of the implantation surface. 
     
     
         9 . The prosthetic device of  claim 7 , wherein the recess surface includes a substantially arcuate portion. 
     
     
         10 . The prosthetic device of  claim 7 , wherein the at least one recess includes an additional recess surface configured to form a space for receiving bone between the additional recess surface and the inner surface. 
     
     
         11 . The prosthetic device of  claim 1 , wherein the at least one recess includes a sidewall with at least two portions for engaging bone to constrain the body portion in the at least two translational degrees of freedom. 
     
     
         12 . The prosthetic device of  claim 1 , wherein the constraint structure is configured to constrain the prosthetic device in the bone in the absence of adhesive. 
     
     
         13 . The prosthetic device of  claim 1 , wherein the prosthetic device is one of a tibial implant and a femoral implant configured to be implanted in a respective one of a tibia and femur to form a portion of a knee joint. 
     
     
         14 . The prosthetic device of  claim 13 , wherein the at least one of the tibial implant and the femoral implant includes a plurality of the compressive projections projecting from a lateral side portion of the implantation surface. 
     
     
         15 . The prosthetic device of  claim 13 , wherein the at least one of the tibial implant and the femoral implant includes the at least one interlock projection projecting from a bottom side portion of the implantation surface. 
     
     
         16 . The prosthetic device of  claim 13 , wherein the at least one of the tibial implant and the femoral implant includes the at least one recess in a bottom side portion of the implantation surface. 
     
     
         17 . The prosthetic device of  claim 1 , wherein the prosthetic device is an acetabular cup configured to be implanted in a pelvis to form a portion of a hip joint. 
     
     
         18 . The prosthetic device of  claim 17 , wherein the acetabular cup includes the at least one recess, wherein the at least one recess includes a sidewall with at least two portions for engaging bone to constrain the body portion in the at least two translational degrees of freedom. 
     
     
         19 . The prosthetic device of  claim 1 , wherein the prosthetic device is a femoral stem configured to be implanted in a femur to form a portion of a hip joint. 
     
     
         20 . The prosthetic device of  claim 19 , wherein the femoral stem includes a plurality of the compressive projections projecting from a lateral side portion of the implantation surface. 
     
     
         21 . A method for planning bone removal for implantation of a prosthetic device into bone, comprising:
 storing data representative of a prosthetic device in a computer readable medium, wherein the prosthetic device includes a body portion having an implantation surface configured to face the bone upon implantation and at least one feature that provides a constraint structure that will constrain the prosthetic device in the bone; and   defining, based on the data, at least one bone-cutting pattern for (i) removing a first portion of bone in a first area sufficient to seat the body portion and (ii) at least one of removing and maintaining a second portion of bone in a second area configured to interact with the constraint structure.   
     
     
         22 . The method of  claim 21 , wherein the defining of the at least one bone-cutting pattern includes removing a portion of the second portion of bone, while maintaining a portion of the second portion of bone to provide at least one projection configured to engage the implantation surface to provide a compressive force between the projection and implantation surface and constrain the prosthetic device. 
     
     
         23 . The method of  claim 22 , wherein the defining of the at least one bone-cutting pattern includes maintaining a portion of the second portion of bone to provide a plurality of projections configured to engage the implantation surface to provide a compressive force between the projection and implantation surface and constrain the prosthetic device. 
     
     
         24 . The method of  claim 21 , wherein the defining of the at least one bone-cutting pattern includes maintaining a portion of the second portion of bone to provide a projection that is configured to project into a recess in the prosthetic device forming at least a portion of the constraint structure. 
     
     
         25 . The method of  claim 21 , wherein the defining of the at least one bone-cutting pattern includes removing a portion of the second portion of bone to provide a recess that is configured to receive a projection from the prosthetic device forming at least a portion of the constraint structure. 
     
     
         26 . The method of  claim 21 , further comprising displaying information representative of the at least one bone-cutting pattern. 
     
     
         27 . A robotic system for preparing a bone to receive a prosthetic device, the robotic system comprising:
 a controllable guide structure configured to guide cutting of the bone into a shape for receiving the prosthetic device;   a computer readable medium for storing data representative of the prosthetic device, wherein the prosthetic device includes a body portion having an implantation surface configured to face the bone upon implantation and at least one feature that provides a constraint structure that will constrain the prosthetic device in the bone; and   a control system for controlling the guide structure, wherein the control system is configured to define at least one bone-cutting pattern for (i) removing a first portion of bone in a first area sufficient to seat the body portion and (ii) at least one of removing and maintaining a second portion of bone in a second area configured to interact with the constraint structure.   
     
     
         28 . The robotic system of  claim 27 , wherein the control system is configured to define the at least one bone-cutting pattern by removing a portion of the second portion of bone, while maintaining a portion of the second portion of bone to provide at least one projection configured to engage the implantation surface to provide a compressive force between the projection and implantation surface and constrain the prosthetic device. 
     
     
         29 . The robotic system of  claim 28 , wherein the control system is configured to define the at least one bone-cutting pattern to maintain a portion of the second portion of bone to provide a plurality of projections configured to engage the implantation surface to provide a compressive force between the projection and implantation surface and constrain the prosthetic device. 
     
     
         30 . The robotic system of  claim 27 , wherein the control system is configured to define the at least one bone-cutting pattern to maintain a portion of the second portion of bone to provide a projection that is configured to project into a recess in the prosthetic device forming at least a portion of the constraint structure. 
     
     
         31 . The robotic system of  claim 27 , wherein the control system is configured to define the at least one bone-cutting pattern to remove a portion of the second portion of bone to provide a recess that is configured to receive a projection from the prosthetic device forming at least a portion of the constraint structure. 
     
     
         32 . The robotic system of  claim 27 , further comprising a display, wherein the control system displays information representative of the at least one bone-cutting pattern on the display.