Kinematic Alignment and Novel Femoral and Tibial Prosthetics

Abstract

A tibial component placement guide for use in a knee arthroplasty procedure involving a knee joint comprising a tibia, a patella, and a femur, the tibial component placement guide comprising an overlay configured to be overlaid a resected tibia that typifies at least one of a shape and an outline of the resected tibia, the overlay including at least one of an indicia and an opening indicative of at least one of an orientation and a position of a presurgical kinematic axis of at least one of the femur and the patella.

Description

CROSS REFERENCE TO RELATED APPLICATIONS[0001]The present application is a continuation of U.S. Nonprovisional patent application Ser. No. 15 / 627,844, titled “KINEMATIC ALIGNMENT OF FEMORAL AND TIBIAL COMPONENTS,” filed Jun. 20, 2017, now U.S. Pat. No. 11,045,330, which is a continuation of U.S. Nonprovisional patent application Ser. No. 14 / 686,685, titled “KINEMATIC ALIGNMENT OF FEMORAL AND TIBIAL COMPONENTS,” filed Apr. 14, 2015, now U.S. Pat. No. 9,901,463, which claims the benefit of U.S. Provisional Patent Application Ser. No. 61 / 979,034, titled “KINEMATIC ALIGNMENT OF FEMORAL AND TIBIAL COMPONENTS,” filed Apr. 14, 2014, and U.S. Provisional Patent Application Ser. No. 62 / 013,198, titled “KINEMATIC ALIGNMENT OF FEMORAL AND TIBIAL COMPONENTS,” filed Jun. 17, 2014, and U.S. Provisional Patent Application Ser. No. 62 / 022,894, titled “KINEMATIC ALIGNMENT OF FEMORAL AND TIBIAL COMPONENTS,” filed Jul. 10, 2014, the disclosure of each of which is incorporated herein by reference.INTROD...

AI Technical Summary

Benefits of technology

The patent describes two methods for analyzing the motion of the knee joint using images. The first method involves using homogeneous transformations to convert the position of one frame to another. The second method involves tracking the contact paths of the femur on the tibia during different movements of the joint. These methods can provide accurate and reproducible results, even with automation. The technical effects of this patent are improved understanding and analysis of knee joint motion for various applications such as medical diagnosis and treatment.

Problems solved by technology

Knee arthritis causes debilitating pain affecting activities of daily living.

Prosthetic placement in TKA is a complex problem related to the complex shapes of the femur and tibia, out of plane geometrical relationships of the articular surfaces and bones, and the additive factor of ligamentous changes, anatomical variation and deformity resulting from chronic disease.

A logical conclusion is that detrimental joint overloads can result from combined rotational and axial malalignment.

While distal measured resection methods attempt to restore “normal” anatomy, by placing implants in the “normal” position using mechanical alignment, this fails to account for underlying rotational deformities.

In addition, the cuts that are made to the femur and tibia during TKA may change the angle and the level of natural joint line causing abnormal tightening or slackening of the collateral, retinacular, and posterior cruciate ligaments and abnormal kinematics.

The undesirable consequences of the abnormal kinematics are instability, motion loss, accelerated component wear and component loosening from uneven load-sharing between compartments.

However, the motion of the knee joint is more complex than a simple hinge joint, and can include translation as well as rotation about other axes.

However in this method the morphology of the femoral condyles and tibial plateaus were never studied properly with kinematics.

No currently available TKA consistently reproduces the kinematic pattern observed in the normal knee.

Along with the inability to provide native kinematics, most patients having TKA fail to achieve full function when compared with a sex and age matched group.

Furthermore, there is an absence of evaluating the effect of standard surgical techniques (e.g., gap balance) on joint kinematics.

Images