Failure Analysis of a Ceramic Bearing Acetabular Component
Notice bibliographique
Résumé
BACKGROUND: Alternative bearings have been explored in an attempt to improve the longevity of total hip prostheses. A Food and Drug Administration (FDA)-approved clinical study of a nonmodular acetabular component consisting of a porous metal shell, compression-molded polyethylene, and a ceramic liner inlay was discontinued following reports of early failures. METHODS: Between October 1999 and January 2003, 429 patients were enrolled in a prospective study to evaluate a cementless ceramic-on-ceramic total hip arthroplasty design (Hedrocel ceramic bearing cup; Implex, Allendale, New Jersey). Two hundred and eighty-two patients (315 hips) were treated with the experimental acetabular implant and 147 patients (157 hips) were treated with an acetabular implant that consisted of the same porous shell but an allpolyethylene liner. Clinical data including a Harris hip score and responses to the Short Form-12 (SF-12) health survey were collected preoperatively and at twelve and twenty-four months postoperatively. Serial radiographs were made preoperatively; at six weeks, three months, six months, and twelve months postoperatively; and annually thereafter. Retrieval analysis was performed on all failed explanted components. Failure was defined as fracture or displacement of the ceramic liner out of the acetabular component. In addition, biomechanical testing was performed on unimplanted acetabular components and mechanically altered cups in an effort to recreate the mechanisms of failure. Finite element analysis was used to estimate stress and strain within the ceramic liner under extreme physiologic loading conditions. RESULTS: The ceramic liner failed in fourteen of the 315 experimental acetabular components; all of the failures were at the ceramic-polyethylene interface. Patients with a body weight of >91 kg had a 4.76 times greater odds of the ceramic liner failing than those who weighed < or =91 kg. Retrieval analysis demonstrated stripe and rim wear with evidence of adhesive wear, indicating a potentially high-friction interaction at the articulation. Finite element analysis demonstrated that the forces on the ceramic liner in cups subjected to extreme loading conditions were insufficient to cause fracture. Biomechanical testing was unable to reproduce an initial ceramic liner displacement in vitro; however, when the ceramic liner was forcibly displaced prior to biomechanical testing, complete displacement and eventual fracture of the ceramic liner resulted. CONCLUSIONS: We hypothesized that the combination of a high patient body weight, an extensive range of motion, and subluxation of the femoral head led to high friction at the articulation between the femoral head and the rim of the liner, which initiated displacement of the ceramic liner. Subsequent normal gait led to further displacement of the liner in all of the fourteen failed components and eventually to ceramic fracture in twelve of the fourteen components.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,002 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,001 | 0,001 |
| Bibliométrie | 0,001 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,000 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».