Systems and methods for providing lightweight prosthetic components

Abstract

Methods for forming prosthetic implants, including femoral implants, are discussed. While the methods can include any suitable step, in some cases, they include providing a master negative mold defining an internal space shaped to form a femoral component configured to replace a distal portion of a femur, wherein the femoral component comprises at least one of: an anterior flange that is disposed at an anterior proximal end of the femoral component, and a proximal extension disposed at a proximal portion of a posterior condyle of the femoral component, the proximal extension comprising a concave articulation surface that is configured to articulate against at least one of: a tibial prosthetic component and a tibia; filling the master negative mold with a molding material to form a molded femoral component; and removing at least one of: the anterior flange, and the proximal extension from the molded femoral component to form a modified molded femoral component. Other implementations are described.

Description

RELATED APPLICATIONS[0001]This application claims priority to U.S. Provisional Patent Application No. 62 / 150,756 (Attorney Docket No. 15379.47), filed Apr. 21, 2015, entitled SYSTEMS AND METHODS FOR PROVIDING LIGHTWEIGHT PROSTHETIC IMPLANTS, which is incorporated herein in its entirety by reference.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]The present invention relates to prostheses, including, without limitation, knee prostheses. In particular, some implementations of the present invention relate to systems and methods for providing prosthetic implants that are relatively lightweight. While the implants can be produced in any suitable manner and have any suitable feature that allows them to be lightweight, in some instances, such implants include an internal lattice structure that supports the implants, while allowing the implants to be relatively lightweight and rigid.[0004]2. Background and Related Art[0005]Orthopedic surgeons are experiencing a proliferatio...

AI Technical Summary

Benefits of technology

[0019]Additionally, some aspects of the present invention relate to systems and methods for providing deeper knee flexion capabilities for knee prosthesis patients, and more particularly by effectuating one or more of the following: (i) providing a greater articular surface area to the femoral component of a knee prosthesis, with either a modification of, or an attachment to the femoral component of a knee prosthesis, which when integrated with a patient's femur and an appropriate tibial component, results in full functional flexion; (ii) providing modifications to the internal geometry of the femoral component and the opposing femoral bone with methods of implanting; (iii) providing asymmetrical under surfaces on the tibial component of the knee prosthesis and uniquely-positioned articular surfaces to facilitate full functional flexion; (iv) providing asymmetrical femoral condylar surfaces with a lateralized patellar (trochlear) groove to more closely replicate physiologic loading of the knee and to provide better tracking of the patella; (v) resectioning essentially all of the anterior femoral articular cartilage and underlying bone, but no additional bone and replacing it with a femoral component that does not have an anterior flange as seen on contemporary prostheses; (vi) providing a femoral component having a modular stem, which allows the femoral component to be rolled onto a resected portion of a distal end of the femur, or to be slid onto the resected portion of the femur at an angle that intersects with a longitudinal axis of the femur; (vii) cutting a posterior proximal portion of a femoral condyle to allow for deep knee flexion; and (viii) providing a process for providing customized prosthetics.

[0022]Implementation of the present invention takes place in association with improved knee prostheses that enable knee prosthesis patients to achieve greater deep knee flexion than previously achievable using presently-designed knee prostheses. In at least some implementations of the present invention, greater deep knee flexion is provided to the knee prosthesis by resecting portions of the femur to allow additional clearance for the posterior horn of the medial meniscus and the tibia. In other implementations in which a portion of the tibia is replaced by a prosthesis, however, the posterior horn is left intact. Additionally, at least some implementations of the present invention further provide positioning and / or installing an articular surface within resectioned portions of the femur to provide an interface between the posterior horn of the medial meniscus and the resectioned surface of the femur.

[0023]In at least some implementations of the present invention, greater deep knee flexion is provided to the knee prosthesis by providing an articular surface on the proximal, anterior surface (or portion) of the posterior condyles of the femur. At least some implementations of the present invention embrace an additional or increased articular surface on the proximal, anterior portion of either or both of the medial or lateral posterior condyles of the femoral component of the prosthesis. Embodiments of the femoral component add increased articular surface area to the proximal end of the posterior condyles of the femoral component in an anterior direction such that when the patient bends his or her knee during deep knee flexion, contact between the femoral component and the tibial component is maintained, and a greater, deeper knee flexion can be achieved.

[0024]In at least some implementations of the present invention, greater deep knee flexion can be provided or improved by modifying the tibial articulation, in which the center of the conforming medial tibial articular surface of the tibial component of the prosthesis is moved posterior relative to what is currently available. Additionally, in some such embodiments, the overall shape of the lateral tibial articular surface is modified.

Problems solved by technology

Unfortunately, some of today's knee prostheses still have shortcomings.

Among these shortcomings is the inability of a knee prosthesis patient to achieve deep knee flexion, also known as full functional flexion.

Though some currently available knee prostheses allow for knee flexion (i.e., bending) of more than 130° from full limb extension (0° being when the patient's knee is fully extended and straight); some such prostheses do not allow patients to flex from full extension to 160° and beyond (e.g., to full functional and / or deep knee flexion).

Most conventional knee prosthesis patients are unable to consistently achieve the latter position or any position placing the knee joint at angles above 130° (e.g., at 160° and beyond).

For many people, such a limb and body position is not often achieved or desired most of the time.

Unfortunately, those with currently-available knee prostheses are unable to participate in any activity requiring greater knee flexion and are thus limited to watching from the sidelines.

For instance, in some Asian and Indian cultures, full functional flexion and the squatting position is common and performed for relatively long periods of time.

In this regard, as such a bone may experience less of the flexion forces than would typically strengthen the bone, such a bone may actually become weak and resorb.

Additionally, in some cases as the bone surrounding a rigid shaft flexes, micro-abrasions may occur at the interface between the bone and the stem, resulting in the loss of bone at the interface.

As a result, some such prostheses may do little to prevent fractures from forming and spreading in the femur (e.g., at stress risers created as a consequence of bone cuts that were made to allow the femoral prosthesis to be seated on the femur).

As yet another example, although some femoral prostheses comprise a stem to strengthen the femur's distal end, such stems often place significant limits on the physical characteristics of the femoral prosthesis that can be used therewith.

Additionally, in some cases in which a femoral prosthesis includes a stem, the stem can also limit the manner in which the femoral prosthesis can be attached to a femur.

Thus, while techniques currently exist that relate to prosthetic implants (such as knee prostheses), challenges with such implants still exist, including those discussed above.

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