Etude Biomécanique du Couple de Frottement Céramique-Céramique dans les Prothèses Totales de Hanche sans Ciment

The purpose of the work in this thesis was to deepen the knowledge on the use of the friction torque ceramic-ceramic in modern cementless hip implant. The clinical study of 100 total hip arthroplasties without cement with a decline of 9 years has shown the reliability of ceramic friction torque in terms of wear, biocompatibility and osseointegration. Thereafter, the comparison of the method of implantation of the implants (with or without impaction of adding additional screws) showed that the rigidity of the ceramic is not inconsistent with a single impaction, for patients who do not exhibit bone fragility. We then studied a particular complication of ceramic grinding or squeaking. An in vitro study of the phenomenon, allowed to reproduce this phenomenon in conditions of optimum lubrication, with the presence of a third metal body between the friction surfaces, suggesting the importance of lubrication in the genesis of the phenomenon. The explant analysis confirmed our hypothesis, highlighting the importance of drawing implants to avoid conflicts that generate prosthetic metal particles. Finally, the analysis of the long-term phenomenon of squeaking showed its low impact on implant survival and quality of life of patients. This work, which involved clinical and biomechanical analysis confirms us in the use of ceramics as frictional torque in total hip arthroplasty without cement, emphasizes the importance of the design and positioning of implants to avoid complications may occur and provides insight into the problem of squeaking and its consequences.Le but du travail réalisé dans cette thèse était d’approfondir les connaissances en matière d’utilisation du couple de frottement céramique-céramique dans l’implantologie moderne de hanche sans ciment. L’étude clinique de 100 prothèses totales de hanche sans ciment avec un recul de 9 ans a permis de montrer la fiabilité du couple de frottement céramique en terme d’usure, de biocompatibilité et d’ostéointégration. Par la suite, la comparaison de la méthode d’implantation de ces implants (impaction avec ou sans adjonction de vis supplémentaires) a montré que la rigidité de la céramique n’était pas incompatible avec une impaction simple, pour des patients qui ne présentent pas de fragilité osseuse. Nous avons ensuite étudié plus particulièrement une complication de la céramique, le grincement ou squeaking. Une étude in vitro du phénomène, a permis de reproduire ce phénomène dans des conditions de lubrification optimale, avec la présence d’un troisième corps métallique entre les surfaces de frottement, suggérant l’importance de la lubrification dans la genèse du phénomène. L’analyse d’explant a conforté notre hypothèse, mettant en évidence l’importance du dessin des implants afin d’éviter les conflits prothétiques pouvant générer des particules métalliques. Enfin, l’analyse sur le long terme du phénomène de squeaking a montré son faible impact sur la survie des implants et sur la qualité de vie des patients. Ce travail, qui a associé des analyses cliniques et biomécaniques nous conforte dans l’utilisation de la céramique comme couple de frottement dans les prothèses totales de hanche sans ciment, insiste sur l’importance du dessin et du positionnement des implants pour éviter les complications qui peuvent survenir et permet de mieux connaître le problème du squeaking et ses conséquences

Biomechanical strudy of ceramic on ceramic cementless total hip arthroplasty

Le but du travail réalisé dans cette thèse était d’approfondir les connaissances en matière d’utilisation du couple de frottement céramique-céramique dans l’implantologie moderne de hanche sans ciment. L’étude clinique de 100 prothèses totales de hanche sans ciment avec un recul de 9 ans a permis de montrer la fiabilité du couple de frottement céramique en terme d’usure, de biocompatibilité et d’ostéointégration. Par la suite, la comparaison de la méthode d’implantation de ces implants (impaction du métal-back avec ou sans adjonction de vis supplémentaires) a montré que la rigidité de la céramique n’était pas incompatible avec une impaction simple du métal-back, pour des patients qui ne présentent pas de fragilité osseuse. Nous avons ensuite étudié plus particulièrement une complication de la céramique, le grincement ou squeaking. Une étude in vitro du phénomène, a permis de reproduire ce phénomène dans des conditions de lubrification optimale, avec la présence d’un troisième corps métallique entre les surfaces de frottement, suggérant l’importance des problèmes de lubrification dans la genèse du phénomène. L’analyse d’explant a conforté notre hypothèse, mettant en évidence l’importance du dessin des implants afin d’éviter les conflits prothétiques pouvant générer des particules métalliques. Enfin, l’analyse sur le long terme du phénomène de squeaking a montré son faible impact sur la survie des implants et sur la qualité de vie des patients. Ce travail, qui a associé des analyses cliniques et biomécaniques nous conforte dans l’utilisation de la céramique comme couple de frottement dans les prothèses totales de hanche sans ciment, insiste sur l’importance du dessin et du positionnement des implants pour éviter les complications qui peuvent survenir et permet de mieux connaître le problème du squeaking et ses conséquencesThe aim of the study done in this thesis was to enhance the knowledge in the use of ceramic on ceramic bearing for cementless total hip arthroplasty. A clinical study of 100 cementless total hip arthroplasty at 9 years of follow-up showed the reliability of ceramic in terms of wear, biocompatibility and osseointegration. Subsequently, the comparison of the method for implantation of the implants (press-fit with or without additional screws fixations) showed that the stiffness of ceramic was not inconsistent with a simple impaction, for patients who do not present bone fragility. We then studied a particular complication of ceramic bearing, the squeaking noise. An in vitro study of this phenomenon, allowed us to reproduce squeaking in lubricated conditions, with the presence of a third metal body between the frictions surfaces, suggesting the importance on lubrication damages in the genesis of this phenomenon. Analysis of explants has confirmed our hypothesis, highlighting the importance of implant design, to avoid impingement, potentially generating metal particles. Finally, the long-term analysis of squeaking phenomenon showed its low impact on implant survival and patient’s quality of life. This work, which involved clinical and biomechanical analysis, confirms the interest for the use of ceramics bearings in total hip arthroplasty, emphasizes the importance of implant design and implant positioning, to avoid complications, and helps for a better understanding with the problem of squeaking and its consequence

Etude rétrospective de 100 prothèses totales de hanche non cimentées à couple de frottement céramique/céramique (résultats à 9 ans)

LYON1-BU Santé (693882101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Indicateurs du développement durable des transports et concertation avec le public : postures stratégiques et argumentations

Réalisé sur la base de l'analyse d'expériences françaises, étrangères et internationales d'indicateurs du développement durable des transports, ce travail montre la pertinence d'une lecture des outils proposés, fondée sur la recherche des postures argumentatives qui les sous-tendent. Trois postures sont ainsi repérables au sein de ces divers travaux : une posture intégratrice visant à l'internalisation des effets externes des transports ; une posture critique, d'inspiration environnementale, interpellant le monde des transports à l'aide de critères externes à ses préoccupations premières ; enfin, une posture globalisante et désincarnée, abordant les transports au travers d'une approche de développement durable d'une nation. L'intérêt analytique de ces trois postures a été confirmé par la mise en évidence des arguments échangés à l'occasion de quatre expériences de participation du public. En conclusion, l'article appelle à mieux définir les modes de gouvernance auxquels s'adressent les expériences d'indicateurs, afin que ces derniers participent plus activement à l'enrichissement des débats portant sur ces politiques publiques structurantes

Use of a Dual Mobility Socket to Manage Total Hip Arthroplasty Instability

Unconstrained tripolar hip implants provide an additional bearing using a mobile polyethylene component between the prosthetic head and the outer metal shell. Such a design increases the effective head diameter and therefore is an attractive option in challenging situations of unstable total hip arthroplasties. We report our experience with 54 patients treated using this dual mobility implant in such situations. We ascertained its ability to restore and maintain stability, and examined component loosening and component failure. At a minimum followup of 2.2 years (mean, 4 years; range, 2.2–6.8 years), one hip had redislocated 2 months postoperatively and was managed successfully without reoperation by closed reduction with no additional dislocation. Two patients required revision of the implant because of dislocation at the inner bearing. Technical errors were responsible for these failures. Three patients had reoperations for deep infections. The postoperative radiographs at latest followup showed very satisfactory osseointegration of the acetabular component because no radiolucent line or osteolysis was reported. Use of this unconstrained tripolar design was successful in restoring and maintaining hip stability. We observed encouraging results at short-term followup regarding potential for loosening or mechanical failures

Nine years follow-up of 100 ceramic-on-ceramic total hip arthroplasty

The aim of this study was to evaluate the first 100 cementless ceramic-on-ceramic total hip arthroplasty (THA) performed at our institution with more than nine years of follow-up. Clinical evaluation was performed using Harris hip score. Radiological evaluation was performed by two surgeons. Four patients were lost to follow-up. Harris hip score significantly improved at latest follow-up. Radiological analysis showed calcar osteolysis for 75 patients and one cup loosening. One patient required a revision five years postoperatively for cup loosening. Based on these results and the routine use of a navigation system to optimise positioning of the implants, we advocate the use of uncemented hydroxyapatite coated ceramic-onceramic THA in young and active patients in our current practice

Hip Squeaking: A 10-Year Follow-Up Study

The aim of the study was to analyze the incidence of squeaking with ceramic-onceramic total hip arthroplasty (THA) after 10 years of follow-up and the potential complications that could occur related to this phenomenon. One hundred THAs implanted between November 1999 and December 2000 were evaluated. Incidence of squeaking was investigated clinically with a questionnaire. Implant positioning was analyzed on x-rays and computer tomography. Of the 100 THAs, 5 patients presented with squeaking. All of them were active, sporty, and heavy men. Functional scores were comparable with nonsqueaking patients. There was no malpositioning on the x-ray analysis, no wear, and no loosening. We could not demonstrate any relation between squeaking and ceramic fracture. Squeaking noise appeared at a mean of 66 months postsurgery. It appears to be an isolated phenomenon without any consequences at 10-year follow-up

Retrieval analysis of squeaking ceramic implants: Are there related specific features?

Ceramic-on-ceramic total hip arthroplasty is routinely used for young and active patients with end stage of hip osteoarthritis. However, squeaking noise is a recently identified problem with such bearing surface. Many in vivo and in vitro studies have been conducted trying to find the potential causes of this phenomenon. However, we are not aware of any study analyzing retrieved ceramic implants for squeaking. Our primary hypothesis was that the surface analysis of retrieved ceramic implants with squeaking would present interesting deteriorations that could explain the squeaking noise. Nine retrieved squeaking implants from ceramic-on-ceramic total hip arthroplasty that were retrieved for various reasons (two exclusively for squeaking, four for recurrent dislocation, one for aseptic loosening and two for instability) were analyzed. Implant positioning was calculated, macroscopic damages were noticed and microscopic roughness was analyzed. The retrieved implants were then tested on a hip simulator reproducing flexion/extension motions in several situations in lubricated and non-lubricated conditions in order to reproduce squeaking. Five cups were considered with borderline insufficient anteversion. Gross impingement damage was visible on seven implants. All the retrieved heads had visible metal transfer on their surface. Eight implants had visible stripe wear. Microscopic analysis showed roughness higher than six microns on the retrieved heads. Squeaking was reproduced in vitro in dry conditions. In lubricated conditions, squeaking did not occur for the retrieved hips. This retrieval analysis suggests that problems of cup orientation and design which can lead to impingement can generate lubrication problems because of metal transfer plus/minus stripe wear which is a common theme in ceramic-on-ceramic bearings that squeak. Squeaking; - Total hip arthroplasty; - Ceramic; - Surface bearing; - Metal transfer; - Stripe wea

Use of a dual mobility socket to manage total hip arthroplasty instability, Clinical Orthopaedics and Related Research 467

Abstract Unconstrained tripolar hip implants provide an additional bearing using a mobile polyethylene component between the prosthetic head and the outer metal shell. Such a design increases the effective head diameter and therefore is an attractive option in challenging situations of unstable total hip arthroplasties. We report our experience with 54 patients treated using this dual mobility implant in such situations. We ascertained its ability to restore and maintain stability, and examined component loosening and component failure. At a minimum followup of 2.2 years (mean, 4 years; range, 2.2-