# US 10,478,307 B2 · Knee prosthesis including rotatable post > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,478,307 B2 - Document ID: US10478307B2 - Status: Granted - Kind: B2 - Application number: 15/892,011 - Filed: 2018-02-08 - Published: 2019-08-08 - Granted: 2019-11-19 - Earliest claimed: 2018-02-08 - Assignees: WM Innovations, LLC - Applicants: Wm Innovations, LLC - Inventors: Ray C. Wasielewski; Stephen Edward White - Web page: https://patentgrep.com/patent/US10478307B2 ## CPC - A61F 2/389: {Tibial components (A61F2/3868 takes precedence)} - A61F 2/3859: {Femoral components} - A61F 2/3886: {for stabilising knees against anterior or lateral dislocations} - A61F 2002/30621: {Features concerning the anatomical functioning or articulation of the prosthetic joint} - A61F: FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS (dental prosthetics A61C) ## Abstract A knee joint prosthesis for a tibia and femur can include a tibial component, a tibial bearing, and a post. The tibial bearing can include a first bearing portion, a second bearing portion, and an aperture. The first bearing portion can be positionable on a first side of the sagittal axis and can have a first shape. The second bearing portion can be positionable on a second side can have a second shape different than the first shape. The post, together with the first bearing portion and the second bearing portion, can be configured to promote the femur to pivot substantially about the first bearing portion. ## Claims ### Claim 1 A knee joint prosthesis for a human tibia and femur, the knee joint prosthesis comprising: a tibial component comprising: a tibial baseplate comprising a proximal surface including a sagittal axis, and an opposing distal surface; and a tibial stem extending from the distal surface of the tibial baseplate and including a cavity therein; a tibial bearing disposable on the proximal surface of the tibial baseplate, the tibial bearing comprising: a first bearing portion positionable on a first side of the sagittal axis and having a first shape; a second bearing portion positionable on a second side of the sagittal axis and having a second shape different than the first shape; and an aperture alignable with the cavity of the tibial stem; a post extendable through the aperture of the tibial bearing and disposable in the cavity of the tibial component, the post rotatable relative to the tibial baseplate and the tibial bearing, the post together with the first bearing portion and the second bearing portion configured to promote the femur to substantially pivot about the first bearing portion; and a collar extending radially from the post and engageable with the tibial baseplate around the cavity and engageable with the bearing aperture to limit movement of the femur along a coronal plane of the femur. ### Claim 2 (depends on 1) The knee joint prosthesis of claim 1, wherein the post and the tibial bearing are shaped to promote asymmetric anteroposterior rollback of a lateral femoral condyle of the femur at a faster rate than rollback of a medial femoral condyle. ### Claim 3 (depends on 1) The knee joint prosthesis of claim 1, wherein the first bearing portion is a medial portion of the bearing. ### Claim 4 (depends on 1) The knee joint prosthesis of claim 1, wherein the first shape of the first portion of the tibial bearing comprises a first radius of curvature that is smaller than a second radius of curvature of the second shape of the second portion of the tibial bearing. ### Claim 5 (depends on 1) The knee joint prosthesis of claim 1, wherein rotation of the post relative to the tibial bearing is limited by contact between the post and the bearing. ### Claim 6 (depends on 1) The knee joint prosthesis of claim 1, the post further comprising: a medial side that is substantially flat; a lateral side opposing the medial side, the lateral side being substantially flat to allow rollback; an anterior face connecting the medial side and the lateral side; and a posterior face opposing the anterior face and connecting the medial side and the lateral side. ### Claim 7 (depends on 6) The knee joint prosthesis of claim 6, wherein rotation of the post relative to the tibial bearing is limited by contact between the bearing and edges of the medial side of the post and edges of the lateral side of the post. ### Claim 8 (depends on 6) The knee joint prosthesis of claim 6, wherein movement of the post out of the cavity is limited by contact between the bearing and the anterior face of the post. ### Claim 9 (depends on 6) The knee joint prosthesis of claim 6, wherein the anterior face is tapered as the post extends superiorly. ### Claim 10 A knee joint prosthesis for a human tibia and femur, the knee joint prosthesis comprising: a tibial component comprising: a tibial baseplate comprising a proximal surface including a sagittal axis, and an opposing distal surface; and a tibial stem extending from the distal surface of the tibial baseplate and including a cavity therein; a tibial bearing disposable on the proximal surface of the tibial baseplate, the tibial bearing comprising: a first bearing portion positionable on a first side of the sagittal axis and having a first shape; a second bearing portion positionable on a second side of the sagittal axis and having a second shape different than the first shape; and an aperture alignable with the cavity of the tibial stem; a post extendable through the aperture of the tibial bearing and disposable in the cavity of the tibial component, the post rotatable relative to the tibial baseplate and the tibial bearing, the post together with the first bearing portion and the second bearing portion configured to promote rotation of the femur with a medial bias; and a collar extending radially from the post and engageable with the tibial baseplate around the cavity and engageable with the bearing aperture to limit movement of the femur along a coronal plane of the femur. ### Claim 11 (depends on 10) The knee joint prosthesis of claim 10, wherein the tibial baseplate further comprises a baseplate PCL notch, and wherein the tibial bearing further comprises a bearing PCL notch alignable with the baseplate PCL notch when the bearing is disposed on the tibial baseplate, the baseplate PCL notch and the bearing PCL notch configured to receive a PCL therein. ### Claim 12 (depends on 10) The knee joint prosthesis of claim 10, wherein the post is free to rotate entirely within the cavity and the aperture. ### Claim 13 (depends on 10) The knee joint prosthesis of claim 10, wherein the post is insertable through the aperture of the tibial bearing and into the cavity of the tibial baseplate after the bearing is disposed on the tibial plate. ### Claim 14 (depends on 10) The knee joint prosthesis of claim 10, wherein the post and the first shape of the first bearing portion and the second shape of the second bearing portion of the tibial bearing are configured to limit translation of the femur relative to the tibia along a transverse plane. ### Claim 15 (depends on 10) The knee joint prosthesis of claim 10, wherein the post and the tibial bearing are shaped to promote asymmetric anteroposterior rollback of a lateral femoral condyle of the femur at a faster rate than rollback of a medial femoral condyle. ### Claim 16 (depends on 10) The knee joint prosthesis of claim 10, wherein the first shape of the first portion of the tibial bearing comprises a first radius of curvature that is smaller than a second radius of curvature of the second shape of the second portion of the tibial bearing. ### Claim 17 A knee joint prosthesis assembly for a human tibia and femur, the knee joint prosthesis comprising: a tibial component comprising: a tibial baseplate comprising a proximal surface including a sagittal axis, and an opposing distal surface; and a tibial stem extending from the distal surface of the tibial baseplate and including a cavity therein; a tibial bearing disposable on the proximal surface of the tibial baseplate, the tibial bearing comprising: a first bearing portion positionable on a first side of the sagittal axis and having a first shape; a second bearing portion positionable on a second side of the sagittal axis and having a second shape different than the first shape; and an aperture alignable with the cavity of the tibial stem; and a post extendable through the aperture of the tibial bearing and disposable in the cavity of the tibial component, the post rotatable relative to the tibial baseplate and the tibial bearing; a femoral component including a lateral condyle, a medial condyle, and an intercondylar fossa disposed between the lateral and medial condyles, the femoral component articulable on the tibial bearing; and a collar extending radially from the post and engageable with the tibial baseplate around the cavity and engageable with the bearing aperture to limit movement of the femur along a coronal plane of the femur wherein the post together with the first bearing portion and the second bearing portion are configured to promote the femur to promote rollback of the lateral femoral condyle. ### Claim 18 (depends on 17) The knee joint prosthesis of claim 17, wherein the post is selectable from a plurality of posts to provide a desired amount of movement of the femoral component relative to the tibial bearing along a coronal plane of the femur. ### Claim 19 (depends on 17) The knee joint prosthesis of claim 17 wherein the tibial bearing is selectable from a plurality of tibial bearings to provide a desired amount of medial bias of rotation of the medial condyle about the tibial bearing. ### Claim 20 (depends on 17) The knee joint prosthesis of claim 17, wherein the tibial bearing is selectable from a plurality of tibial bearings to provide an ability to insert the post without removing the tibial bearing.