Conclusions Revisions and reoperations are more frequent and occur earlier with metal-on-metal hip resurfacing , except when discontinued devices are removed from the analyses .
Background Metal-on-metal hip resurfacing was developed for younger , active patients as an alternative to THA , but it remains controversial .
Study heterogeneity , inconsistent outcome definitions , and unst and ardized outcome measures challenge our ability to compare arthroplasty outcomes studies .
Questions / purpose sWe asked how early revisions or reoperations ( within 5 years of surgery ) and overall revisions , adverse events , and postoperative component malalignment compare among studies of metal-on-metal hip resurfacing with THA  among patients with hip osteoarthritis .
Secondarily , we compared the revision frequency identified in the systematic review with revisions reported in four major joint replacement registries .
The Bimetric cementless total hip replacement: 7–18 year follow-up assessing the influence of acetabular design on survivorship
The purpose of this study was to evaluate the mid- to long-term survivorship of Bimetric cementless total hip replacement and assess how it is affected by the acetabular design . This was a retrospective analysis of 127 Bimetric cementless total hip replacements in 110 patients with a follow-up of 7–18 years . A single design stem and three different cementless metal-backed acetabular design s were used . Patients were assessed clinical ly using the Harris hip score and radiologically by independent review of current hip radiographs . There was only one case of aseptic loosening of the femoral stem . The earliest acetabular design showed a high failure rate whilst the latter two design s showed a 96 % survivorship at a mean of 9.5 years . We conclude that a combination of the bimetric stem with either of the latter acetabular cup design s has a good mid- to long-term performance . Résumél’étude de l’évaluation à moyen ou à long terme de la survie d’une prothèse sans cimentde type Bimétric . il s’agit d’une étude prospect i ve de 127 prothèses totales de hanche chez110 patients avec un suivi moyen de 7 à 18 ans . Un seul dessin de tige fémorale et troisdessins différents de cupule métal back sans ciment ont été utilisés . Les patients ont étéévalués sur le plan clinique ( score de Harris ) et sur le plan radiologique . Un seul cas de descellement aseptique de tige fémorale a été retrouvé . Sur les troismodèles de cupule , le premier modèle montre un taux d’échec très important alors que les deuxderniers modèles ont un taux de survie de 96 % à 9,5 ans de recul . En conclusion , nous pouvons affirmer que la combinaison d’une tige de type bimétric associéeaux modèles acétabulaires les plus tardifs ont permis un bon résultat moyen à long terme
Conclusions Revisions and reoperations are more frequent and occur earlier with metal-on-metal hip resurfacing , except when discontinued devices are removed from the analyses .
Background Metal-on-metal hip resurfacing was developed for younger , active patients as an alternative to THA , but it remains controversial .
Study heterogeneity , inconsistent outcome definitions , and unst and ardized outcome measures challenge our ability to compare arthroplasty outcomes studies .
Questions / purpose sWe asked how early revisions or reoperations ( within 5 years of surgery ) and overall revisions , adverse events , and postoperative component malalignment compare among studies of metal-on-metal hip resurfacing with THA  among patients with hip osteoarthritis .
Secondarily , we compared the revision frequency identified in the systematic review with revisions reported in four major joint replacement registries .