A novel ceramic tibial component is as safe as its metal counterpart

2018 ◽  
Vol 63 (3) ◽  
pp. 327-332 ◽  
Author(s):  
Klemens Trieb
Keyword(s):  
Tibial Component ◽  
Maximum Load ◽  
Load Test ◽  
Strength Testing ◽  
Burst Strength ◽  
Total Knee ◽  
Material Fracture ◽  
Set Up ◽  
Further Development

Abstract Failure rates of 2–10% provide evidence for further development in knee arthroplasty. The purpose of our study was to examine the safety of the tibial component of a novel all-ceramic total knee replacement (TKR) (BPK-S Integration ceramic) consisting of BIOLOX®delta ceramic. The standards ISO 14879-1 and ASTM F1800-07 describe the test set-up for the experimental strength verification with a significantly increased maximum load of 5300 N (900 N are required) and post-fatigue burst strength testing. All specimens were able to prove their mechanical strength against fracture in the alternating load test. There was no material fracture in any of the included tibial components. The subsequent post-fatigue burst strength testing revealed the maximum strength against fracture of all specimens. With at least 9.7 kN for size 3 and at least 12.1 kN for size 6, all specimens showed relatively large strength reserves to the stress in the alternating load test. So far we simulated an in vivo lifetime of 10 years for the tibial component. Further studies should be conducted in which longer in vivo lifetimes of the components are simulated to investigate possible fatigue of the used material over a longer period of time.

scholarly journals In Vivo Kinematic Analysis of Bicruciate-retaining Total Knee Arthroplasty Focused on Function of the ACL

2021 ◽  
Author(s):  
Kosei Ishigaki ◽  
Hideyuki Aoki ◽  
Ryo Takamatsu ◽  
Yuji Nishiwaki ◽  
Hiroshi Takahashi ◽  
...  
Keyword(s):  
Total Knee Arthroplasty ◽  
Femoral Component ◽  
Knee Arthroplasty ◽  
Kinematic Analysis ◽  
Tibial Component ◽  
Lateral Translation ◽  
In Vivo Kinetics ◽  
Total Knee ◽  
Bcr Tka

Abstract Background: The utility of a bi-cruciate retaining total knee arthroplasty (BCR-TKA) is uncertain. In this study, we performed an in vivo kinematic analysis of squat motion on level ground and on a downward slope in patients treated with BCR-TKA to examine the value of anterior cruciate ligament (ACL) preservation.Methods: The subjects were ten valgus knees that underwent TKA (BCR: 5 knees, CR: 5 knees) at our hospital. We evaluated in vivo kinematics of the knee using fluoroscopy and investigated the femoral component translation relative to the tibial component from extension to maximum flexion, and the rotation angle between the components under the two conditions. Statistical analysis was conducted by Mann-Whitney U test to compare the rotational angle, the location of lateral and medial contact points per flexion angle. Differences in these parameters between the BCR and CR groups across the flexion angles were compared by repeated measures ANOVA.Results: Rotation of the femoral component to the tibial component occurred gradually as flexion continued. On level ground, lateral rotation at 0° to 120° flexion was 14.5±1.95° in the BCR group and 7.9±0.47° in the CR group. Medial translation was 4.1±1.73mm in the BCR group and 2.5±1.64mm in the CR group, and lateral translation was 13.2±1.6mm in the BCR group and 7.1±1.74mm in the CR group. On a forward slope, lateral rotation was 12.7±1.45° in the BCR group and 7.57±0.47° in the CR group. Medial translation was 5.87±1.78mm in the BCR and 2.9±0.81mm in the CR, and lateral translation was 13.6±1.84mm in the BCR and 7.4±0.96mm in the CR.Conclusion: An in vivo kinetics analysis of deep flexion motion was conducted on level ground and on a forward slope to stress the ACL. Under both conditions, kinetics close to screw home movement were found in the BCR group and rotation was significantly larger than that in the CR group. The medial contact point between components was located significantly more anterior in the BCR group. In conclusion, BCR-TKA was found to have in vivo kinetics close to those of a normal knee, in comparison with CR-TKA.

scholarly journals Influence of tibial component posterior slope on in vivo knee kinematics in fixed-bearing total knee arthroplasty

2006 ◽  
Vol 24 (4) ◽  
pp. 581-587 ◽  
Author(s):  
F. Catani ◽  
S. Fantozzi ◽  
A. Ensini ◽  
A. Leardini ◽  
D. Moschella ◽  
...  
Keyword(s):  
Total Knee Arthroplasty ◽  
Knee Arthroplasty ◽  
Tibial Component ◽  
Knee Kinematics ◽  
Fixed Bearing ◽  
Posterior Slope ◽  
Total Knee ◽  
In Vivo Knee Kinematics

In Vivo Knee Kinematics for a Cruciate Sacrificing Total Knee Arthroplasty Having Both a Symmetrical Femoral and Tibial Component

2020 ◽  
Vol 35 (6) ◽  
pp. 1712-1719 ◽  
Author(s):  
Milad Khasian ◽  
Michael T. LaCour ◽  
Seth C. Coomer ◽  
Michael P. Bolognesi ◽  
Richard D. Komistek
Keyword(s):  
Total Knee Arthroplasty ◽  
Knee Arthroplasty ◽  
Tibial Component ◽  
Knee Kinematics ◽  
Total Knee ◽  
In Vivo Knee Kinematics

An Optimized Image Matching Method for Determining In-Vivo TKA Kinematics with a Dual-Orthogonal Fluoroscopic Imaging System

2006 ◽  
Vol 128 (4) ◽  
pp. 588-595 ◽  
Author(s):  
Jeffrey Bingham ◽  
Guoan Li
Keyword(s):  
Femoral Component ◽  
Tibial Component ◽  
Degrees Of Freedom ◽  
Imaging System ◽  
Matching Algorithm ◽  
Translational Accuracy ◽  
Fluoroscopic Imaging ◽  
Total Knee ◽  
Accuracy And Repeatability

This study presents an optimized matching algorithm for a dual-orthogonal fluoroscopic image system used to determine six degrees-of-freedom total knee arthroplasty (TKA) kinematics in-vivo. The algorithm was evaluated using controlled conditions and standard geometries. Results of the validation demonstrate the algorithm’s robustness and capability of realizing a pose from a variety of initial poses. Under idealized conditions, poses of a TKA system were recreated to within 0.02±0.01 mm and 0.02±0.03 deg for the femoral component and 0.07±0.09 mm and 0.16±0.18 deg for the tibial component. By employing a standardized geometry with spheres, the translational accuracy and repeatability under actual conditions was found to be 0.01±0.06 mm. Application of the optimized matching algorithm to a TKA patient showed that the pose of in-vivo TKA components can be repeatedly located, with standard deviations less than ±0.12 mm and ±0.12 deg for the femoral component and ±0.29 mm and ±0.25 deg for the tibial component. This methodology presents a useful tool that can be readily applied to the investigation of in-vivo motion of TKA kinematics.

Continuous Quantitative Monitoring of Mural, Platelet-Dependent, Thrombus Kinetics in the Crushed Rat Femoral Vein

1991 ◽  
Vol 65 (04) ◽  
pp. 425-431 ◽  
Author(s):  
F Stockmans ◽  
H Deckmyn ◽  
J Gruwez ◽  
J Vermylen ◽  
R Acland
Keyword(s):  
Thrombus Formation ◽  
Femoral Vein ◽  
Maximum Size ◽  
Digital Analysis ◽  
Video Recordings ◽  
Quantitative Monitoring ◽  
Set Up ◽  
Kinetics Of ◽  
Quantitative Nature

SummaryA new in vivo method to study the size and dynamics of a growing mural thrombus was set up in the rat femoral vein. The method uses a standardized crush injury to induce a thrombus, and a newly developed transilluminator combined with digital analysis of video recordings. Thrombi in this model formed rapidly, reaching a maximum size 391 ± 35 sec following injury, after which they degraded with a half-life of 197 ± 31 sec. Histological examination indicated that the thrombi consisted mainly of platelets. The quantitative nature of the transillumination technique was demonstrated by simultaneous measurement of the incorporation of 111In labeled platelets into the thrombus. Thrombus formation, studied at 30 min interval in both femoral veins, showed satisfactory reproducibility overall and within a given animalWith this method we were able to induce a thrombus using a clinically relevant injury and to monitor continuously and reproducibly the kinetics of thrombus formation in a vessel of clinically and surgically relevant size

Rapid, Refined, and Robust Method for Expression, Purification, and Characterization of Recombinant Human Amyloid-beta M1-42

2019 ◽  
Author(s):  
Priya Prakash ◽  
Travis Lantz ◽  
Krupal P. Jethava ◽  
Gaurav Chopra
Keyword(s):  
Amyloid Beta ◽  
Western Blots ◽  
Force Microscopy ◽  
E Coli ◽  
Atomic Force ◽  
Set Up ◽  
Short Time

Amyloid plaques found in the brains of Alzheimer’s disease (AD) patients primarily consists of amyloid beta 1-42 (Ab42). Commercially, Ab42 is synthetized using peptide synthesizers. We describe a robust methodology for expression of recombinant human Ab(M1-42) in Rosetta(DE3)pLysS and BL21(DE3)pLysS competent E. coli with refined and rapid analytical purification techniques. The peptide is isolated and purified from the transformed cells using an optimized set-up for reverse-phase HPLC protocol, using commonly available C18 columns, yielding high amounts of peptide (~15-20 mg per 1 L culture) in a short time. The recombinant Ab(M1-42) forms characteristic aggregates similar to synthetic Ab42 aggregates as verified by western blots and atomic force microscopy to warrant future biological use. Our rapid, refined, and robust technique to purify human Ab(M1-42) can be used to synthesize chemical probes for several downstream in vitro and in vivo assays to facilitate AD research.

scholarly journals A System-Agnostic, Adaptable and Extensible Animal Support Cradle System for Cardio-Respiratory-Synchronised, and Other, Multi-Modal Imaging of Small Animals

Tomography ◽  
2021 ◽  
Vol 7 (1) ◽  
pp. 39-54
Author(s):  
Veerle Kersemans ◽  
Stuart Gilchrist ◽  
Philip Danny Allen ◽  
Sheena Wallington ◽  
Paul Kinchesh ◽  
...  
Keyword(s):  
Scientific Data ◽  
Cardiac Monitoring ◽  
Small Animals ◽  
Maintenance System ◽  
Wide Range ◽  
Set Up ◽  
Animal Handling ◽  
Imaging Performance ◽  
Significant Effort

Standardisation of animal handling procedures for a wide range of preclinical imaging scanners will improve imaging performance and reproducibility of scientific data. Whilst there has been significant effort in defining how well scanners should operate and how in vivo experimentation should be practised, there is little detail on how to achieve optimal scanner performance with best practices in animal welfare. Here, we describe a system-agnostic, adaptable and extensible animal support cradle system for cardio-respiratory-synchronised, and other, multi-modal imaging of small animals. The animal support cradle can be adapted on a per application basis and features integrated tubing for anaesthetic and tracer delivery, an electrically driven rectal temperature maintenance system and respiratory and cardiac monitoring. Through a combination of careful material and device selection, we have described an approach that allows animals to be transferred whilst under general anaesthesia between any of the tomographic scanners we currently or have previously operated. The set-up is minimally invasive, cheap and easy to implement and for multi-modal, multi-vendor imaging of small animals.

scholarly journals Osseointegration of a novel dental implant in canine

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Lingxiao Wang ◽  
Zhenhua Gao ◽  
Yucheng Su ◽  
Qian Liu ◽  
Yi Ge ◽  
...  
Keyword(s):  
Volume Ratio ◽  
Volume Density ◽  
Scientific Basis ◽  
Bone Volume ◽  
Trabecular Thickness ◽  
Bone Implant ◽  
Further Development ◽  
Trabecular Number ◽  
Histological Staining

AbstractThis study aimed to compare and verify the osseointegration performance of a novel implant (NI) in vivo, which could provide a useful scientific basis for the further development of NIs. Thirty-two NIs treated with hydrofluoric acid and anodization and sixteen control implants (CIs) were placed in the mandibles of 8 beagles. Micro-CT showed that the trabecular number (Tb.N) significantly increased and trabecular separation (Tb.Sp) significantly decreased in the NIs at 2 weeks. Significant differences were found in the trabecular thickness, Tb.N, Tb.Sp, bone surface/bone volume ratio, and bone volume/total volume ratio between the two groups from the 2nd–4th weeks. However, there were no significant differences between the two groups in the bone volume density at 2, 4, 8, or 12 weeks or bone-implant contact at 2 or 4 weeks, but the BIC in the CIs was higher than that in the NIs at the 8th and 12th weeks. Meanwhile, the histological staining showed a similar osseointegration process between the two groups over time. Overall, the NIs could be used as new potential implants after further improvement.

scholarly journals Multiple screening approaches reveal HDAC6 as a novel regulator of glycolytic metabolism in triple-negative breast cancer

2021 ◽  
Vol 7 (3) ◽  
pp. eabc4897
Author(s):  
Catríona M. Dowling ◽  
Kate E. R. Hollinshead ◽  
Alessandra Di Grande ◽  
Justin Pritchard ◽  
Hua Zhang ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Triple Negative Breast Cancer ◽  
Histone Deacetylase Inhibitors ◽  
Triple Negative ◽  
Mitochondrial Apoptosis ◽  
Glycolytic Metabolism ◽  
Set Up ◽  
Screening Approaches

Triple-negative breast cancer (TNBC) is a subtype of breast cancer without a targeted form of therapy. Unfortunately, up to 70% of patients with TNBC develop resistance to treatment. A known contributor to chemoresistance is dysfunctional mitochondrial apoptosis signaling. We set up a phenotypic small-molecule screen to reveal vulnerabilities in TNBC cells that were independent of mitochondrial apoptosis. Using a functional genetic approach, we identified that a “hit” compound, BAS-2, had a potentially similar mechanism of action to histone deacetylase inhibitors (HDAC). An in vitro HDAC inhibitor assay confirmed that the compound selectively inhibited HDAC6. Using state-of-the-art acetylome mass spectrometry, we identified glycolytic substrates of HDAC6 in TNBC cells. We confirmed that inhibition or knockout of HDAC6 reduced glycolytic metabolism both in vitro and in vivo. Through a series of unbiased screening approaches, we have identified a previously unidentified role for HDAC6 in regulating glycolytic metabolism.

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