The Influence of Kinematic Conditions and Variations in Component Positioning on the Severity of Edge Loading and Wear of Ceramic-on-Ceramic Hip Bearings

Dynamic separation and direct edge loading of hip replacement bearings can be caused by many factors, including implant positioning, implant design, changes in device over time, surgical variations and patient variations. Such dynamic separation and direct edge loading can lead to increased wear. Different input kinematic conditions have been used for experimental hip simulator studies to produce clinically relevant elliptical contact wear paths between the bearings during gait. The aim of this study was to investigate the influence of input kinematics (two axes of rotation simulation conditions (without abduction/adduction) and three axes of rotation simulation conditions (with abduction/adduction and different loading profiles) and variations in component positioning (different levels of medial-lateral translational mismatch at standard and steep cup inclination angles) on the occurrence, severity of edge loading, dynamic separation and wear of size 36 mm ceramic-on-ceramic hip bearings on an electromechanical hip joint simulator. The results showed that, overall, either of the two axes or three axes input profiles were equally valid in providing a suitable preclinical testing method for assessing the occurrence and severity of edge loading and wear under edge loading conditions. In terms of component positioning, as cup inclination and medial-lateral translational mismatch increased, so did dynamic separation, axial load at the rim, severity of edge loading and wear.

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Potential New Treatments for Knee OA: A Prospective Review of Registered Trials

Applied Sciences ◽

10.3390/app112211049 ◽

2021 ◽

Vol 11 (22) ◽

pp. 11049

Author(s):

Marius Ioniţescu ◽

Dinu Vermeşan ◽

Bogdan Andor ◽

Cristian Dumitrascu ◽

Musab Al-Qatawneh ◽

...

Keyword(s):

Implant Design ◽

Artery Embolization ◽

Disease Modifying Drugs ◽

Cell Therapies ◽

Knee Oa ◽

Design Changes ◽

Osteoarthritis Knee ◽

New Treatments ◽

New Procedures ◽

Fast Track Recovery

We aimed to evaluate potential new treatments for knee osteoarthritis (OA). The National Institute of Health ClinicalTrials.gov database was searched for “Osteoarthritis, Knee”. We found 565 ongoing interventional studies with a total planned enrollment of 111,276 subjects. Ongoing studies for knee OA represent a very small fraction of the registered clinical trials, but they are over a quarter of all knee trials and over two thirds of all OA studies. The most researched topic was arthroplasty, with aspects such as implant design changes, cementless fixation, robotic guidance, pain management, and fast track recovery. Intraarticular injections focused on cell therapies with mesenchymal stem cells sourced from adipose tissue, bone marrow, or umbilical cord. We could see the introduction of the first disease modifying drugs with an impact on knee OA, as well as new procedures such as geniculate artery embolization and geniculate nerve ablation.

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Biotribological behaviour of Vitamin E-blended highly cross-linked UHMWPE in a hip joint simulator

Industrial Lubrication and Tribology ◽

10.1108/ilt-09-2015-0130 ◽

2016 ◽

Vol 68 (5) ◽

pp. 548-553 ◽

Cited By ~ 2

Author(s):

Guomei Chen ◽

Zifeng Ni ◽

Shanhua Qian ◽

Yongwu Zhao

Keyword(s):

Wear Resistance ◽

Vitamin E ◽

Hip Joint ◽

Oxidative Degradation ◽

Test Environment ◽

Content Type ◽

Artificial Hip Joint ◽

Hip Simulator ◽

Directional Motion ◽

Hip Joint Simulator

Purpose The purposes of this paper are to investigate the biotribological behaviour of Vitamin E-blended highly cross-linked ultra-high molecular weight polyethylene (HXL-UHMWPE) under multi-directional motion by using a CUMT II artificial joint hip simulator and compare it with HXL-UHMWPE and conventional UHMWPE. Design/methodology/approach The biotribological behaviour of conventional, highly cross-linked and Vitamin E-blended highly cross-linked UHMWPE acetabular cups counterfaced with CoCrMo alloy femoral head under multi-directional motion were investigated by using CUMT-II artificial hip joint simulator for one-million walking cycles. The test environment was at 36.5 ± 0.5°C and 25 per cent bovine serum was used as lubricant. A Paul cycle load with a peak of 784 N was applied; the motion and loading were synchronized at 1 Hz. Findings The wear resistance of Vitamin E-blended highly cross-linked UHMWPE was significantly higher than that of highly cross-linked and conventional UHMWPE. The wear marks observed from the worn surface of UHMWPE were multi-directional, with no dominant wear direction. Only abrasion occurred on the surface of Vitamin E-blended highly cross-linked UHMWPE, while yielding and accumulated plastic flow processes occurred on the surface of conventional UHMWPE and flaking-like facture and abrasion occurred on the surface of highly cross-linked UHMWPE. Originality/value Besides the prevention of oxidative degradation, blending with Vitamin E can also reduce the incidence of fatigue crack occurred in the surface layer of HXL-UHMWPE samples. Therefore, the wear resistance of HXL-UHMWPE under multi-directional motion can be further enhanced by blending with Vitamin E.

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A systematic review of robotic-assisted unicompartmental knee arthroplasty

The Bone & Joint Journal ◽

10.1302/0301-620x.101b7.bjj-2018-1317.r1 ◽

2019 ◽

Vol 101-B (7) ◽

pp. 838-847 ◽

Cited By ~ 22

Author(s):

P. G. Robinson ◽

N. D. Clement ◽

D. Hamilton ◽

M. J. G. Blyth ◽

F. S. Haddad ◽

...

Keyword(s):

Systematic Review ◽

United Kingdom ◽

Knee Arthroplasty ◽

Unicompartmental Knee Arthroplasty ◽

Functional Outcomes ◽

Implant Design ◽

Current Evidence ◽

Robotic Assisted ◽

Implant Positioning ◽

Unicompartmental Knee

AimsRobotic-assisted unicompartmental knee arthroplasty (UKA) promises accurate implant placement with the potential of improved survival and functional outcomes. The aim of this study was to present the current evidence for robotic-assisted UKA and describe the outcome in terms of implant positioning, range of movement (ROM), function and survival, and the types of robot and implants that are currently used.Materials and MethodsA search of PubMed and Medline was performed in October 2018 in line with the Preferred Reporting Items for Systematic Review and Meta-Analysis statement. Search terms included “robotic”, “knee”, and “surgery”. The criteria for inclusion was any study describing the use of robotic UKA and reporting implant positioning, ROM, function, and survival for clinical, cadaveric, or dry bone studies.ResultsA total of 528 articles were initially identified from the databases and reference lists. Following full text screening, 38 studies that satisfied the inclusion criteria were included. In all, 20 studies reported on implant positioning, 18 on functional outcomes, 16 on survivorship, and six on ROM. The Mako (Stryker, Mahwah, New Jersey) robot was used in 32 studies (84%), the BlueBelt Navio (Blue Belt Technologies, Plymouth, Minnesota) in three (8%), the Sculptor RGA (Stanmore Implants, Borehamwood United Kingdom) in two (5%), and the Acrobot (The Acrobot Co. Ltd., London, United Kingdom) in one study (3%). The most commonly used implant was the Restoris MCK (Stryker). Nine studies (24%) did not report the implant that was used. The pooled survivorship at six years follow-up was 96%. However, when assessing survival according to implant design, survivorship of an inlay (all-polyethylene) tibial implant was 89%, whereas that of an onlay (metal-backed) implant was 97% at six years (odds ratio 3.66, 95% confidence interval 20.7 to 6.46, p < 0.001).ConclusionThere is little description of the choice of implant when reporting robotic-assisted UKA, which is essential when assessing survivorship, in the literature. Implant positioning with robotic-assisted UKA is more accurate and more reproducible than that performed manually and may offer better functional outcomes, but whether this translates into improved implant survival in the mid- to longer-term remains to be seen. Cite this article: Bone Joint J 2019;101-B:838–847.

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Edge loading in third generation alumina ceramic-on-ceramic bearings

The Journal of Arthroplasty ◽

10.1016/j.arth.2003.09.018 ◽

2004 ◽

Vol 19 (4) ◽

pp. 402-413 ◽

Cited By ~ 182

Author(s):

William L Walter ◽

Gerard M Insley ◽

William K Walter ◽

Michael A Tuke

Keyword(s):

Alumina Ceramic ◽

Third Generation ◽

Edge Loading ◽

Ceramic On Ceramic

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Direct evidence of lubrication in ceramic-on-ceramic total hip replacements

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1243/0954406011520706 ◽

2001 ◽

Vol 215 (3) ◽

pp. 265-268 ◽

Cited By ~ 8

Author(s):

S L Smith ◽

D Dowson ◽

A A J Goldsmith ◽

R Valizadeh ◽

J S Colligon

Keyword(s):

Squeeze Film ◽

Asperity Contact ◽

Surface Separation ◽

Total Hip Replacements ◽

Hip Simulator ◽

Hip Replacements ◽

Acetabular Components ◽

Thin Conducting Film ◽

Film Lubrication ◽

Ceramic On Ceramic

A study of surface contact and separation of ceramic-on-ceramic joints was undertaken in 25 per cent bovine serum using a hip simulator. An electrical resistivity technique was used to detect the extent of surface separation throughout a complete walking cycle. The femoral and acetabular components were coated in a thin conducting film of titanium nitride to allow application of the resistivity technique to non-conducting ceramic. Surface separation of the acetabular and femoral components was detected throughout each simulated walking cycle. Fluctuations in the applied voltage across the joint were observed which could not be attributed to elastohydrodynamic or squeeze-film lubrication effects. The probable cause of the voltage fluctuations was brief and occasional contact between the surfaces caused by a combination of asperity contact and subsequent detachment of the conductive coating.

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Wear of novel ceramic‐on‐ceramic bearings under adverse and clinically relevant hip simulator conditions

Journal of Biomedical Materials Research Part B Applied Biomaterials ◽

10.1002/jbm.b.32965 ◽

2013 ◽

Vol 101 (8) ◽

pp. 1456-1462 ◽

Cited By ~ 30

Author(s):

Mazen Al‐Hajjar ◽

Louise M. Jennings ◽

Sabine Begand ◽

Thomas Oberbach ◽

Daniel Delfosse ◽

...

Keyword(s):

Hip Simulator ◽

Ceramic On Ceramic

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Technique and Accuracy Assessment of a Novel Image-Free Handheld Robot for Knee Arthroplasty in Bi-Cruciate Retaining Total Knee Replacement

10.29007/4rzz ◽

2018 ◽

Cited By ~ 2

Author(s):

Branislav Jaramaz ◽

Riddhit Mitra ◽

Constantinos Nikou ◽

Cynthia Kung

Keyword(s):

Total Knee Replacement ◽

Knee Replacement ◽

Accuracy Assessment ◽

Disease Patient ◽

Implant Design ◽

Cruciate Retaining ◽

Virtual Tools ◽

Implant Positioning ◽

Accuracy And Precision ◽

Total Knee

Bi-cruciate retaining knee implants are anatomically designed for use in early surgical intervention, for patients with less severe arthritic disease. Patient satisfaction after total knee replacement is directly related to knee stability and proprioception, particularly for high-demand, active patients. While preservation of all intact and healthy ligaments may be the key to achieving such results of satisfaction, balancing four ligaments in a bi-cruciate procedure is more technically challenging then a conventional total knee replacement. Robotics-assisted arthroplasty has been gaining popularity as a tool to increase accuracy and precision of implant positioning. Robotics-assisted systems can provide surgeons with virtual tools to make informed decisions for knee replacement, specific to the needs of the patient. Here, we are introducing a semiautonomous handheld robotic system support for a bi-cruciate retaining knee implant design. The system supports image-free anatomic data collection and streamlined intraoperative surgical planning with dynamic gap balancing before any bone preparation. In this study, we evaluate the surgical technique and accuracy of implant placement in synthetic bone and cadaver experiments.

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