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EP-4734883-A1 - POSTERIOR-STABILIZED ORTHOPAEDIC INSERT AND SYSTEM

EP4734883A1EP 4734883 A1EP4734883 A1EP 4734883A1EP-4734883-A1

Abstract

An orthopaedic knee prosthesis includes a tibial insert (104) including a post (150). The post of the tibial insert includes features that facilitate the medial pivoting of a femoral component through a range of flexion.

Inventors

  • ARAM, LUKE J.
  • ROCK, MICHAEL J.
  • BENNETT, TRAVIS D.
  • WHITE, STEPHEN E.
  • MANE, AMITKUMAR M.

Assignees

  • DePuy Ireland Unlimited Company

Dates

Publication Date
20260506
Application Date
20240626

Claims (20)

  1. 1. An orthopaedic insert comprising: a platform having a lateral articular surface configured to articulate with a lateral condyle of a femoral component and a medial articular surface configured to articulate with a medial condyle of the femoral component, wherein the medial articular surface is asymmetrically shaped relative to the lateral articular surface; and a post extending superiorly from the platform and located between the lateral and medial articular surfaces, wherein the post has a posterior surface, an anterior surface opposite the posterior surface, a lateral sidewall extending from the posterior surface to the anterior surface, and a medial sidewall opposite the lateral sidewall and extending from the posterior surface to the anterior surface, wherein the medial and lateral side walls of the post are concave when viewed in a coronal cross-sectional plane.
  2. 2. The orthopaedic insert of claim 1, wherein a medial -lateral bisecting plane of the post is offset from a medial-lateral bisecting plane of the platform.
  3. 3. The orthopaedic insert of claim 2, wherein the medial -lateral bisecting plane of the post is offset from the medial -lateral bisecting plane of the platform in the lateral direction.
  4. 4. The orthopaedic insert of any of claims 1-3, wherein the medial and lateral side walls of the post are also concave when viewed in a sagittal cross-section plane.
  5. 5. The orthopaedic insert of any of claims 1-4, wherein each of the lateral and medial side walls includes a concave section and an upper end located superiorly to the respective concave section, and wherein the upper end of the medial sidewall defines a vertical plane and the upper end of the lateral sidewall is angled relative to the vertical plane defined by the medial sidewall.
  6. 6. The orthopaedic insert of any of claims 1-5, wherein an angle defined between a medial-lateral bisecting plane of the platform and a first plane tangent to a first point located on the lateral side wall is less than an angle defined by the medial -lateral bisecting plane of the platform and a second plane tangent to a second point located on the medial sidewall, wherein the first point and second point are equidistant from a bottom surface of the platform.
  7. 7. The orthopaedic insert of any of claims 1-6, wherein the lateral articular surface includes a lateral dwell point that defines a distal-most point on the lateral articular surface and the medial articular surface includes a medial dwell point that defines a distal -most point on the medial articular surface, and wherein a posterior -most point on the posterior surface of the post is located posteriorly of the lateral dwell point and of the medial dwell point.
  8. 8. The orthopaedic insert of any of claims 1-6, wherein: the lateral articular surface includes an anterior lateral lip and a lateral dwell point that defines a distal-most point on the lateral articular surface, and wherein an inferiorsuperior distance between the lateral dwell point and a superior -most point of the anterior lateral lip defines a lip height of the anterior lateral lip, and the medial articular surface includes an anterior medial lip and a medial dwell point that defines a distal-most point on the medial articular surface, and wherein an inferiorsuperior distance between the medial dwell point and a superior -most point of the anterior medial lip defines a lip height of the anterior medial lip, wherein the lip height of the anterior medial lip is greater than the lip height of the anterior lateral lip.
  9. 9. The orthopaedic insert of any of claims 1 -8, wherein the posterior surface and each of the lateral sidewall and the medial sidewall forms a pair of posterior comers of the post and wherein the anterior surface and each of the lateral sidewall and the medial sidewall forms a pair of anterior comers of the post, wherein the anterior corners have a greater radius of curvature than the posterior corners.
  10. 10. The orthopaedic insert of any of claims 1-9, wherein the posterior surface of the post has an “S-shaped” coronal cross-section that includes a concave section and a convex section that is superior to the concave section.
  11. 11. The orthopaedic insert of any of claims 1-10, wherein the medial and lateral side walls are also concave when viewed in a transverse cross-sectional plane that bisects the post.
  12. 12. An orthopaedic knee prosthesis, comprising the orthopaedic insert of any of claims 1-11 and a femoral component having a lateral condyle and a medial condyle, wherein each of the lateral condyle and the medial condyle includes a femoral articular surface defined by a plurality of curved femoral surface sections that includes a first curved femoral surface section defined by a continually decreasing radius of curvature.
  13. 13. The orthopaedic knee prosthesis of claim 12, wherein the lateral articular surface of the tibial insert includes a lateral dwell point that defines a distal-most point on the lateral articular surface, and wherein a contact point between the femoral articular surface of the lateral condyle of the femoral component and the lateral articular surface of the tibial insert lies on the lateral dwell point of the lateral articular surface of the tibial insert when the femoral component is positioned in 0 degrees of flexion.
  14. 14. The orthopaedic knee prosthesis of claim 13, wherein the contact point between the femoral articular surface of the lateral condyle of the femoral component and the lateral articular surface of the tibial insert moves posteriorly relative to the lateral dwell point of the lateral articular surface of the tibial insert as the femoral component is moved through a range of flexion.
  15. 15. The orthopaedic knee prosthesis of claim 13 or claim 14, wherein the contact point between the femoral articular surface of the lateral condyle of the femoral component and the lateral articular surface of the tibial insert is located posteriorly of the lateral dwell point of the lateral articular surface of the tibial insert by more than 0.5 millimeters when the femoral component is positioned at 90 degrees of flexion.
  16. 16. An orthopaedic knee prosthesis comprising: a tibial insert including (i) a platform having a lateral articular surface configured to articulate with a lateral condyle of a femoral component and a medial articular surface configured to articulate with a medial condyle of the femoral component, wherein the medial articular surface is asymmetrically shaped relative to the lateral articular surface and (ii) a post that extends superiorly from the platform and is located between the lateral and medial articular surfaces, wherein an angle defined between a medial-lateral bisecting plane of the platform and a first plane tangent to a first point located on the lateral side wall is less than an angle defined by the medial-lateral bisecting plane of the platform and a second plane tangent to a second point located on the medial sidewall, wherein the first point and second point are equidistant from a bottom surface of the platform.
  17. 17. The orthopaedic knee prosthesis of claim 16, further comprising a femoral component having a lateral condyle and a medial condyle, wherein each of the lateral condyle and the medial condyle includes a femoral articular surface defined by a plurality of curved femoral surface sections that includes a first curved femoral surface section defined by a continually decreasing radius of curvature.
  18. 18. The orthopaedic knee prosthesis of claim 17, wherein the lateral articular surface of the tibial insert includes a lateral dwell point that defines a distal-most point on the lateral articular surface, and wherein a contact point between the femoral articular surface of the lateral condyle of the femoral component and the lateral articular surface of the tibial insert lies on the lateral dwell point of the lateral articular surface of the tibial insert when the femoral component is positioned in 0 degrees of flexion.
  19. 19. The orthopaedic knee prosthesis of claim 18, wherein the contact point between the femoral articular surface of the lateral condyle of the femoral component and the lateral articular surface of the tibial insert moves posteriorly relative to the lateral dwell point of the lateral articular surface of the tibial insert as the femoral component is moved through a range of flexion.
  20. 20. The orthopaedic knee prosthesis of claim 18 or claim 19, wherein the contact point between the femoral articular surface of the lateral condyle of the femoral component and the lateral articular surface of the tibial insert is located posteriorly of the lateral dwell point of the lateral articular surface of the tibial insert by more than 0.5 millimeters when the femoral component is positioned at 90 degrees of flexion.

Description

POSTERIOR-STABILIZED ORTHOPAEDIC INSERT AND SYSTEM [0001] The present application claims priority under 35 U.S.C. § 119 to, and the benefit of, U.S. Provisional Patent Application Serial No. 63/524,113, entitled “POSTERIOR- STABILIZED ORTHOPAEDIC SYSTEM FOR MEDIAL PIVOTING OF FEMORAL COMPONENT,” which was filed on June 29, 2023, the entirety of which is expressly incorporated herein by reference. TECHNICAL FIELD [0002] The present disclosure relates to orthopaedic knee prosthesis systems and, more specifically, to posterior-stabilized orthopaedic knee prostheses and methods for total knee arthroplasty procedures. BACKGROUND [0003] Joint arthroplasty is a well-known surgical procedure by which a diseased and/or damaged natural joint is replaced by a prosthetic joint. A typical knee prosthesis includes a tibial tray, a femoral component, a patella component, and a polymer insert or bearing positioned between the tibial tray and the femoral component. Depending on the severity of the damage to the patient’s joint, orthopaedic prostheses of varying mobility may be used. For example, the knee prosthesis may include a “fixed” tibial insert in some cases wherein it is desirable to limit the movement of the knee prosthesis, such as when significant soft tissue damage or loss is present. Alternatively, the knee prosthesis may include a “mobile” tibial insert in cases wherein a greater degree of freedom of movement is desired. Additionally, the knee prosthesis may be a total knee prosthesis designed to replace the femoral -tibial interface of both condyles of the patient’s femur or a uni-compartmental (or uni-condylar) knee prosthesis designed to replace the femoral-tibial interface of a single condyle of the patient’s femur. [0004] The type of orthopedic knee prosthesis used to replace a patient’s natural knee may also depend on whether the patient’s posterior cruciate ligament is retained or sacrificed (i.e., removed) during surgery. For example, if the patient’s posterior cruciate ligament is damaged, diseased, and/or otherwise removed during surgery, a posterior-stabilized knee prosthesis may be used to provide additional support and/or control at later degrees of flexion. [0005] Typical orthopaedic knee prostheses are generally designed to duplicate the natural movement of the patient’s joint. As the knee is flexed and extended, the femoral and tibial components articulate and undergo combinations of relative anterior-posterior motion and relative internal -external rotation. However, the patient’s surrounding soft tissue also impacts the kinematics and stability of the orthopaedic knee prosthesis throughout the joint’s range of motion. That is, forces exerted on the orthopaedic components by the patient’s soft tissue may cause unwanted or undesirable motion of the orthopaedic knee prosthesis. For example, the orthopaedic knee prosthesis may exhibit an amount of unnatural (paradoxical) anterior translation as the femoral component is moved through the range of flexion. SUMMARY [0006] According to one aspect, an orthopaedic insert comprising may include a platform and a post extending superiorly from the platform. The platform may include a lateral articular surface configured to articulate with a lateral condyle of a femoral component and a medial articular surface configured to articulate with a medial condyle of the femoral component. In some embodiments, the medial articular surface may be asymmetrically shaped relative to the lateral articular surface. The post may be located between the lateral and medial articular surfaces. The post may include a posterior surface, an anterior surface opposite the posterior surface, a lateral sidewall extending from the posterior surface to the anterior surface, and a medial sidewall opposite the lateral sidewall and extending from the posterior surface to the anterior surface. The medial and lateral side walls may be concave when viewed in a coronal cross-sectional plane. [0007] In some embodiments, a medial-lateral bisecting plane of the post may be offset from a medial-lateral bisecting plane of the platform. For example, the medial -lateral bisecting plane of the post may be offset from the medial-lateral bisecting plane of the platform in the lateral direction. [0008] Additionally, in some embodiments, the medial and lateral side walls may be also concave when viewed in a sagittal cross-section plane. Additionally, each of the lateral and medial side walls may include a concave section and an upper end located superiorly to the respective concave section. The upper end of the medial sidewall may define a vertical plane and the upper end of the lateral sidewall is angled relative to the vertical plane defined by the medial sidewall. [0009] In some embodiments, an angle defined between a medial -lateral bisecting plane of the platform and a first plane tangent to a first point located on the lateral side wall may be less than an angle defined by the medial-lateral b