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Functional positioning in robotic medial unicompartmental knee arthroplasty: a step-by-step technique
No full textInternational audienceUnicompartmental knee arthroplasty (UKA) compared to total knee arthroplasty, offers several benefits, though it is associated with a higher revision rate, primarily due to suboptimal implant positioning. Recent advances in robotic-assisted techniques have contributed to more personalized and reproducible procedures. Functional Positioning (FP), a three-dimensional alignment concept, introduces a tailored approach based on a surgical technique that is both effective and reproducible. This article presents a step-by-step surgical technique for medial UKA using FP principles in combination with an image-based robotic system. The technique ensures accurate preoperative planning, real-time intraoperative adjustments, and precise component placement. The key steps of this surgical technique include achieving congruent contact points between the femur and tibia under load across the full range of motion, positioning the implant based on the compliance of the medial soft tissues, planning for a targeted laxity that results in an “eagle-wing” appearance, and the use of robotic tools to map cartilage for optimal resurfacing. Future studies will help refine FP strategies and further optimize outcomes in these patients
Statistical Inverse Identification of a Stochastic Phase-Field Model for Brittle Fracture in Random Heterogeneous Elastic Materials
No full textInternational audienceThis work deals with the statistical inverse identification of a stochastic phase-field model for brittle fracture in random heterogeneous elastic media. Within the framework of linear elasticity theory and probability theory, a stochastic model for almost surely isotropic random elasticity fields is constructed using the maximum Entropy (MaxEnt) principle [1, 2] to perform stochastic phase-field fracture simulations. In this work, we consider one of the most widely used phase-field models for brittle fracture of isotropic elastic materials [3] which is classically parameterized by the fracture toughness (or critical energy release rate) and the regularization length (controlling the phase-field/damage localization bandwith). A sensitivity analysis is conducted to investigate the impact of some fracture properties (fracture toughness) and some hyperparameters (dispersion coefficient and spatial correlation length) involved in the stochastic model of random elasticity field on the crack path and the global forcedisplacement response. Finally, a statistical inverse identification method based on a nonparametric Bayesian approach is proposed to estimate the posterior probability distribution of random fracture toughness. The relevance of the proposed approach is assessed on two-dimensional benchmark problems for brittle fracture of a single-edge notched/cracked square domain subjected to (i) a uniaxial tensile test and (ii) a pure shear test.REFERENCES [1] J. Guilleminot and C. Soize. On the Statistical Dependence for the Components of Random Elasticity Tensors Exhibiting Material Symmetry Properties. Journal of Elasticity, 111(2):109-130, 2013.[2] C. Soize. Uncertainty Quantification: An Accelerated Course with Advanced Applications in Computational Engineering, volume 47 of Interdisciplinary Applied Mathematics. Springer International Publishing, 2017.[3] C. Miehe, M. Hofacker, and F. Welschinger. A phase field model for rate-independent crack propagation: Robust algorithmic implementation based on operator splits. Computer Methods in Applied Mechanics and Engineering, 199(45):2765–2778, 2010
Analgesia considerations in orthopaedic surgery: the role of magnesium sulfate infusions
No full textInternational audienceOrthopaedic surgical operations are associated with significant post-operative pain, often managed with opioids, which carry risks of adverse effects and dependency. Magnesium sulfate, a NMDA receptor antagonist with analgesic and muscle relaxant properties, has emerged as a potential adjunct to improve pain control and reduce opioid consumption in orthopaedic procedures. Current evidence supports magnesium sulfate as a valuable adjunct in orthopaedic pain management, particularly in reducing opioid consumption and enhancing muscle relaxation. However, heterogeneity in study design, administration protocols, and patient populations warrants cautious interpretation. Monitoring for side effects such as hypotension and respiratory depression remains essential. Further high-quality, standardized trials are needed to optimize dosing strategies and confirm long-term benefits
Bertrand Lemennicier (1943–2019): défenseur infatigable de la liberté
No full textInternational audienceEditorial paper on the Special issue dedicated to Bertrand LemennicierPrésentation éditoriale du numéro spécial consacré à Bertrand Lemennicie
Analyse des microplastiques en µ-FTIR et Py-GC-MS : deux méthodes complémentaires ?
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L'intelligence artificielle générative d'images dans le secteur de l'illustration des jeux de société
No full textInternational audienceNotre article présente un projet de recherche débuté en novembre 2024 concernant les conséquences de l'intelligence artificielle (IA) générative d'images sur le secteur d'activités du jeu de société et, plus précisément, sur le métier d'illustrateur de jeux de société. Il s'agit donc actuellement d'un travail exploratoire afin d'appréhender les premières tendances comme les travaux de l'association loi 1901 La charte des Illustrateur•rices Ludiques (CIL). Cette réaction d'une profession, principalement composée de travailleurs indépendants, est particulièrement intéressante à étudier à l'aune des concepts de digital undertow et de sociomatérialité forte (Scott & Orlikowski, 2021 ; Orlikowski & Scott, 2023), surtout dans un contexte où l'ensemble du secteur tente de faire reconnaître le jeu de société comme un objet culturel par le législateur
Sensibilisation des étudiants à la gestion de crise cyber
No full textInternational audienceDans le cadre d'un projet tutoré débuté durant l'année universitaire 2023-2024, nous avons conçu et déployé un dispositif pédagogique visant à sensibiliser les étudiants en formation initiale à la gestion de crise cyber. L'objectif est de faire acquérir des connaissances et participer au développement de compétences sur ce sujet grâce à une simulation de situation de crise cyber. Le dispositif de l'année 2024-2025 comprend des scénarios simulés et des retours d'expérience (RETEX) pour ancrer les apprentissages. À la suite d'un questionnaire d'autoévaluation complété par les 108 étudiants, les résultats montrent une meilleure appréhension de la crise cyber et de ses enjeux. Nous avons toutefois identifié plusieurs limites et perspectives d'évolution du dispositif, tant organisationnelles que pédagogiques
Minimum Five-Year Outcomes of Cemented Monobloc Dual Mobility Cups in Revision Total Hip Arthroplasty: High Survival Rates and Enhanced Functional Results with Reinforcement Constructs
No full textInternational audienceBackground: Monobloc dual mobility cups (MDMC) significantly reduce the risk of dislocations, a major complication in revision total hip arthroplasty (RTHA). In RTHA, cementing the acetabular cup may be required, particularly when combined with an acetabular reinforcement. This study aimed to evaluate the survivorship of cemented MDMC in reinforcement constructs in RTHA.Methods: During a 10-year period, we retrospectively evaluated 59 patients undergoing RTHA with a cemented MDMC combined with an acetabular reinforcement construct, with a minimum follow-up of five years. The mean age at surgery was 69 years, the mean BMI was 26.1, and 63.3% were women. Preoperative Harris Hip Score (HHS), indication for revision, and the type of acetabular reconstruction were recorded. Postoperatively, complications and revisions were evaluated. Failure was defined as implant revision, while the HHS was assessed at the final (mean 5.8 years) follow-up.Results: There were 10 failures observed (16.9%): six for periprosthetic joint infection (PJI) (10.2%), three for acetabular aseptic loosening (5.1%), and one for dislocation (1.7%). The 5-year implant survival for any revision was 83.1% (95% Confidence Interval (CI): 70.8 to 90.5), and for septic revision was 89.8% (95% CI: 78.8 to 95.3). and for mechanical failure was 93.2% (95% CI: 82.9 to 97.4). The mean time interval between index surgery and revision was 9.9 months. At the final follow-up, the mean HHS was 82.7 (range, 37 to 100).Conclusions: The use of cemented MDMCs combined with acetabular reinforcement in RTHA seems to be an effective approach for achieving favorable functional outcomes, with a low risk of dislocation or mechanical failure at mid-term (mean 5.8 years) follow-up
