A Direct Comparision of Patient and Simulator Total Knee Replacement Kinematics

2001 ◽  
Author(s):  
John D. DesJardins ◽  
Scott A. Banks ◽  
Lisa C. Benson ◽  
Martine LaBerge
Keyword(s):  
Total Knee Replacement ◽  
Knee Replacement ◽  
Gold Standard ◽  
Patient Population ◽  
International Standards ◽  
Wear Testing ◽  
Wear Simulation ◽  
Total Knee

Abstract The need to critically evaluate the efficacy of current total knee replacement (TKR) wear testing methodologies is great. Proposed international standards for TKR wear simulation have been drafted, yet their validity continues to be debated. The “gold standard” to which all wear testing methodologies should be compared is the measured in vivo TKR performance of the patient population. With the exception of retrieval analyses, few detailed comparisons of in-vitro vs. in-vivo TKR performance have been performed to date. The current study compares simulator TKR wear testing kinematics to measured in vivo TKR kinematics to evaluate the validity of the proposed ISO force-controlled wear testing methodology.

Fiberscopic Visualization of Total Knee Replacement Contact Kinematics During In Vitro Simulation

2005 ◽  
Author(s):  
John DesJardins ◽  
Lisa Gustafson ◽  
Lisa Benson ◽  
Martine LaBerge
Keyword(s):  
Total Knee Replacement ◽  
Knee Replacement ◽  
High Speed ◽  
Wear Behavior ◽  
Video Camera ◽  
Wear Testing ◽  
Imaging Method ◽  
Contact Areas ◽  
Total Knee

Optimization of total knee replacement (TKR) design and wear behavior requires the study of bearing contact mechanics. In this study, a novel fiberscopic imaging method was developed and combined with dynamic TKR simulation to visually quantify dynamic TKR contact areas in vitro. Contact areas between transparent TKR tibial inserts and metallic femoral components were captured using opaque lubricant media and a fiberscopic high-speed video camera within the simulator. Walking and stair descent loading patterns were characterized. Centroid location and contact pathways were calculated to determine pathway velocity and cross-shear characteristics. Overall, contact velocities ranging from 0 to 233mm/sec and crossing angles ranging from near 0 to 90 degrees were found during this study. These results provide a basis for wear testing and cross-shear modeling of TKR materials, leading to more accurate predictions of wear behavior in these implants.

scholarly journals The relationship between alignment, function and loading in total knee replacement: In-vivo analysis of a unique patient population

2020 ◽  
Vol 112 ◽  
pp. 110042 ◽  
Author(s):  
David Williams ◽  
Andrew Metcalfe ◽  
June Madete ◽  
Gemma Whatling ◽  
Peter Kempshall ◽  
...  
Keyword(s):  
Total Knee Replacement ◽  
Knee Replacement ◽  
Patient Population ◽  
Total Knee ◽  
In Vivo Analysis ◽  
The Relationship

scholarly journals Finite element evaluation of the newest ISO testing standard for polyethylene total knee replacement liners

2018 ◽  
Vol 232 (6) ◽  
pp. 545-552 ◽  
Author(s):  
Steven P Mell ◽  
Spencer Fullam ◽  
Markus A Wimmer ◽  
Hannah J Lundberg
Keyword(s):  
Finite Element ◽  
Total Knee Replacement ◽  
Knee Replacement ◽  
External Rotation ◽  
Articular Surface ◽  
Element Model ◽  
International Standards ◽  
Wear Testing ◽  
Contact Conditions ◽  
Total Knee

Current treatment for end-stage osteoarthritis is total knee replacement. Given that the number of total knee replacement surgeries is expected to approach 3.48 million by 2030, understanding long-term failure is important. One of the preclinical tests for total knee replacements is carried out using mechanical wear testing under generic walking conditions. Used for this purpose is the International Standards Organization’s generic walking profile. Recently this standard was updated by reversing the direction of anterior/posterior translation and internal/external rotation. The effects of this change have not been investigated, and therefore, it is unknown if comparisons between wear tests utilizing the old and new version of the standard are valid. In this study, we used a finite element model along with a frictional energy–based wear model to compare the kinematic inputs, contact conditions, and wear from the older and newer versions of the ISO standard. Simulator-tested components were used to validate the computational model. We found that there were no visible similarities in the contact conditions between the old and new versions of the standard. The new version of the standard had a lower wear rate but covered a larger portion of the articular surface. Locations of wear also varied considerably. The results of the study suggest that major differences between the old and new standard exist, and therefore, historical wear results should be compared with caution to newly obtained results.

scholarly journals Knee Flexion and Daily Activities in Patients following Total Knee Replacement: A Comparison with ISO Standard 14243

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Markus A. Wimmer ◽  
William Nechtow ◽  
Thorsten Schwenke ◽  
Kirsten C. Moisio
Keyword(s):  
Total Knee Replacement ◽  
Knee Replacement ◽  
Knee Flexion ◽  
Daily Activities ◽  
Wear Testing ◽  
Significant Difference ◽  
Flexion Extension ◽  
Total Knee ◽  
Stair Walking ◽  
The Many

Walking is only one of many daily activities performed by patients following total knee replacement (TKR). The purpose of this study was to examine the hypotheses (a) that subject activity characteristics are correlated with knee flexion range of motion (ROM) and (b) that there is a significant difference between the subject’s flexion/extension excursion throughout the day and the ISO specified input for knee wear testing. In order to characterize activity, the number of walking and stair stepping cycles, the time spent with dynamic and stationary activities, the number of activity sequences, and the knee flexion/extension excursion of 32 TKR subjects were collected during daily activity. Flexion/extension profiles were compared with the ISO 14243 simulator input profile using a level crossing classification algorithm. Subjects took an average of 3102 (range: 343–5857) walking cycles including 65 (range: 0–319) stair stepping cycles. Active and passive ROMs were positively correlated with stair walking time, stair step counts, and stair walking sequences. Simulated knee motion according to ISO showed significantly fewer level crossings at the flexion angles 20–40° and beyond 50° than those measured with the monitor. This suggests that implant wear testing protocols should contain more cycles and a variety of activities requiring higher knee flexion angles with incorporated resting/transition periods to account for the many activity sequences.

Evaluation of the relationship of tibiofemoral kinematics before and after total knee replacement in an in vitro model of cranial cruciate deficiency in the dog

2016 ◽  
Vol 29 (06) ◽  
pp. 484-490 ◽  
Author(s):  
Rebecca Howie ◽  
Timothy Foutz ◽  
Curtis Cathcart ◽  
Jeff Burmeister ◽  
Steve Budsberg
Keyword(s):  
Total Knee Replacement ◽  
Knee Replacement ◽  
External Rotation ◽  
Cruciate Ligament ◽  
Flexion Extension ◽  
Before And After ◽  
Total Knee ◽  
Tibiofemoral Kinematics ◽  
The Relationship

SummaryObjective: To investigate the relationship between tibiofemoral kinematics before and after total knee replacement (TKR) in vitro.Animals: Eight canine hemipelves.Methods: A modified Oxford Knee Rig was used to place cadaveric limbs through a range of passive motion allowing the kinematics of the stifle to be evaluated. Four measurements were performed: a control stage, followed by a cranial cruciate transection stage, then following TKR with the musculature intact stage, and finally TKR with removal of limb musculature stage. Joint angles and translations of the femur relative to the tibia, including flexion-extension versus adduction-abduction, flexion-extension versus internal-external rotation, as well as flexion-extension versus each translation (cranial-caudal and lateral-medial) were calculated.Results: Significant differences were identified in kinematic data from limbs following TKR implantation as compared to the unaltered stifle. The TKR resulted in significant decreases in external rotation of the stifle during flexion-extension compared to the limb prior to any intervention, as well as increasing the abduction. The TKR significantly increased the caudal translation of the femur relative to the tibia compared to the unaltered limb. When compared with the cranial cruciate ligament-transection stage, TKR significantly decreased the ratio of the external rotation to flexion.Discussion: All three test periods showed significant differences from the unaltered stifle. The TKR did not completely restore the normal kinematics of the stifle.

Combined Wear Behavior and Long-Term Implant-Bone Fixation of Total Knee Replacement: A Novel In Vitro Set-up

2009 ◽  
Vol 34 (5) ◽  
pp. E177-E183 ◽  
Author(s):  
Michele Spinelli ◽  
Saverio Affatato ◽  
Luca Cristofolini ◽  
Paolo Erani ◽  
Domenico Tigani ◽  
...  
Keyword(s):  
Total Knee Replacement ◽  
Knee Replacement ◽  
Wear Behavior ◽  
Bone Fixation ◽  
Total Knee ◽  
Set Up

scholarly journals Urinary Prothrombin Fragment 1+2 in relation to Development of Non-Symptomatic and Symptomatic Venous Thromboembolic Events following Total Knee Replacement

Thrombosis ◽  
2011 ◽  
Vol 2011 ◽  
pp. 1-6
Author(s):  
Lars C. Borris ◽  
Morten Breindahl ◽  
Michael R. Lassen ◽  
Ákos F. Pap
Keyword(s):  
Total Knee Replacement ◽  
Knee Replacement ◽  
Operative Procedure ◽  
Clinical Test ◽  
Prothrombin Fragment ◽  
Venous Thromboembolic Events ◽  
Venous Thromboembolic ◽  
Patients At Risk ◽  
Total Knee

Prothrombin fragment 1+2 is excreted in urine (uF1+2) as a result of in vivo thrombin generation and can be a marker of coagulation status after an operative procedure. This study compared uF1+2 levels in patients with symptomatic and non-symptomatic venous thromboembolism (VTE) after total knee replacement (TKR) and in event-free sex- and age-matched controls. Significantly higher median uF1+2 levels were seen in the VTE patients on days 1, 3, and the day of venography (mostly day 7) after TKR compared with controls. The uF1+2 levels tended to be high in some patients with symptomatic VTE; however, the discriminatory efficacy of the test could not be evaluated. In conclusion, this study showed that patients with VTE tend to have significantly higher uF1+2 levels compared with patients without events between days 1 and 7 after TKR surgery. Measurement of uF1+2 could provide a simple, non-invasive clinical test to identify patients at risk of VTE.

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