Effect of geometric variations on tibiofemoral surface and post-cam design of normal knee kinematics restoration

Introduction: Only 70–85% of patients that had total knee arthroplasty (TKA) are satisfied with their knees. The need for a near to normal knee kinematics is crucial and maybe the solution to their needs. Addressing the cruciate ligaments during surgery along with the extent of arthrosis may give a solution to this problem. Material and methods: One hundred consecutive patients in whom a total knee arthroplasty was indicated and performed were prospectively documented. During the knee replacement surgery, the condition of the anterior and posterior cruciate ligaments and the degree of osteoarthritis (OA) in the medial and lateral compartments as well as in the patello-femoral joint were documented using the Outerbridge classification. The patients’ average age was 72.3 years, with the majority being female. In all patients, a total bi-compartmental knee replacement was indicated. Results: Our results showed that in 78% of all patients the anterior, and in 98% the posterior cruciate ligament was still intact. Seventy-one percent of cases suffered from grade 4 medial osteoarthritis, 19% from grade 3 and 10% from grade 2. Thirty-six of patients suffered from grade 4 lateral osteoarthritis, 36% from grade 3, 24% from grade 2 and 4% from grade 1. Grade 4 patello-femoral osteoarthritis was present in 32% of all patients, grade 3 in 60% and grade 2 in 8% of all patients. Discussion: The goal of arthroplasty is to approximate the function of a normal knee. The retention of the anterior cruciate ligament (ACL) allows for better knee, kinematics, improved proprioception, increased flexion and an overall improvement in knee function. The decreased constraint that is possible with retention of both cruciates may decrease implant stresses and improve the implant survivorship. The distribution of OA shows that the medial and patello-femoral compartments of the joint are primarily affected. This could also allow for a more conservative and patient-tailored prosthetic design.

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Assessment Of Normal Knee Kinematics During Activities Of Daily Living In Older Adults

Medicine & Science in Sports & Exercise ◽

10.1249/01.mss.0000478346.94664.2d ◽

2015 ◽

Vol 47 ◽

pp. 599

Author(s):

Vasiliki Kefala ◽

Adam J. Cyr ◽

Donald R. Hume ◽

Kevin B. Shelburne

Keyword(s):

Older Adults ◽

Activities Of Daily Living ◽

Daily Living ◽

Knee Kinematics ◽

Normal Knee

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Single bundle anterior cruciate reconstruction does not restore normal knee kinematics at 6 months: An upright MRI study

International Journal of Surgery ◽

10.1016/j.ijsu.2011.07.021 ◽

2011 ◽

Vol 9 (7) ◽

pp. 499

Author(s):

Jamie Nicholson ◽

Alasdair Sutherland ◽

Francis Smith

Keyword(s):

Knee Kinematics ◽

Single Bundle ◽

Upright Mri ◽

Normal Knee ◽

Anterior Cruciate ◽

Mri Study

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Effect of Post-Cam Design for Normal Knee Joint Kinematic, Ligament, and Quadriceps Force in Patient-Specific Posterior-Stabilized Total Knee Arthroplasty by Using Finite Element Analysis

BioMed Research International ◽

10.1155/2018/2438980 ◽

2018 ◽

Vol 2018 ◽

pp. 1-11 ◽

Cited By ~ 2

Author(s):

Yong-Gon Koh ◽

Juhyun Son ◽

Oh-Ryong Kwon ◽

Sae Kwang Kwon ◽

Kyoung-Tak Kang

Keyword(s):

Lateral Collateral Ligament ◽

Posterior Stabilized ◽

Collateral Ligament ◽

Element Analysis ◽

Normal Knee ◽

Cam Design ◽

Knee Mechanics ◽

Total Knee ◽

Quadriceps Force ◽

Femoral Rollback

The purpose of this study is to investigate post-cam design via finite element analysis to evaluate the most normal-like knee mechanics. We developed five different three-dimensional computational models of customized posterior-stabilized (PS) total knee arthroplasty (TKA) involving identical surfaces with the exception of the post-cam geometry. They include flat-and-flat, curve-and-curve (concave), curve-and-curve (concave and convex), helical, and asymmetrical post-cam designs. We compared the kinematics, collateral ligament force, and quadriceps force in the customized PS-TKA with five different post-cam designs and conventional PS-TKA to those of a normal knee under deep-knee-bend conditions. The results indicated that femoral rollback in curve-and-curve (concave) post-cam design exhibited the most normal-like knee kinematics, although the internal rotation was the closest to that of a normal knee in the helical post-cam design. The curve-and-curve (concave) post-cam design showed a femoral rollback of 4.4 mm less than the normal knee, and the helical post-cam design showed an internal rotation of 5.6° less than the normal knee. Lateral collateral ligament and quadriceps forces in curve-and-curve (concave) post-cam design, and medial collateral ligament forces in helical post-cam design were the closest to that of a normal knee. The curve-and-curve (concave) post-cam design showed 20% greater lateral collateral ligament force than normal knee, and helical post-cam design showed medial collateral ligament force 14% greater than normal knee. The results revealed the variation in each design that provided the most normal-like biomechanical effect. The present biomechanical data are expected to provide useful information to improve post-cam design to restore normal-like knee mechanics in customized PS-TKA.

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Dynamic MRI Assessment of Normal Knee Kinematics

journal of Clinical & Experimental Orthopaedics ◽

10.4172/2471-8416.100041 ◽

2017 ◽

Vol 03 (03) ◽

Author(s):

Lukas Haug ◽

Daniel L Weber ◽

Daniel Haddad ◽

Patrick Bohm ◽

Maximilian Rudert ◽

...

Keyword(s):

Knee Kinematics ◽

Dynamic Mri ◽

Normal Knee

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Restoration of normal knee kinematics with respect to tibial insert design in mobile bearing lateral unicompartmental arthroplasty using computational simulation

Bone and Joint Research ◽

10.1302/2046-3758.97.bjr-2019-0384.r1 ◽

2020 ◽

Vol 9 (7) ◽

pp. 421-428

Author(s):

Yong-Gon Koh ◽

Jin-Ah Lee ◽

Hyun-Seok Chung ◽

Hyo-Jeong Kim ◽

Kyoung-Tak Kang

Keyword(s):

Internal Rotation ◽

Computational Simulation ◽

Knee Kinematics ◽

Mobile Bearing ◽

High Rate ◽

Inferior Surface ◽

Normal Knee ◽

Tibial Insert ◽

Femoral Rollback

Aims Mobile-bearing unicompartmental knee arthroplasty (UKA) with a flat tibial plateau has not performed well in the lateral compartment, leading to a high rate of dislocation. For this reason, the Domed Lateral UKA with a biconcave bearing was developed. However, medial and lateral tibial plateaus have asymmetric anatomical geometries, with a slightly dished medial and a convex lateral plateau. Therefore, the aim of this study was to evaluate the extent at which the normal knee kinematics were restored with different tibial insert designs using computational simulation. Methods We developed three different tibial inserts having flat, conforming, and anatomy-mimetic superior surfaces, whereas the inferior surface in all was designed to be concave to prevent dislocation. Kinematics from four male subjects and one female subject were compared under deep knee bend activity. Results The conforming design showed significantly different kinematics in femoral rollback and internal rotation compared to that of the intact knee. The flat design showed significantly different kinematics in femoral rotation during high flexion. The anatomy-mimetic design preserved normal knee kinematics in femoral rollback and internal rotation. Conclusion The anatomy-mimetic design in lateral mobile UKA demonstrated restoration of normal knee kinematics. Such design may allow achievement of the long sought normal knee characteristics post-lateral mobile UKA. However, further in vivo and clinical studies are required to determine whether this design can truly achieve a more normal feeling of the knee and improved patient satisfaction. Cite this article: Bone Joint Res 2020;9(7):421–428.

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