Introduction

Ceramic-on-ceramic couplings demonstrated to be reliable bearings in primary total hip arthroplasty (THA), with long-term remarkable results. Like-on-like configurations were widely described. On the contrary, mixed material combinations from the same manufacturer, Delta-on-Forte or Forte-on-Delta, were poorly studied. In particular, it is unknown whether mixed ceramic combinations are more at risk of ceramic fractures. Thus, a registry study was conducted to investigate the long-term survival rates and reasons for revision of mixed ceramic combinations. A comparison with Delta-on-Delta couplings was also performed.

Materials and methods

The regional arthroplasty registry RIPO was enquired about three cohorts of ceramic bearings (head-on-liner: Delta-on-Forte, Forte-on-Delta, Delta-on-Delta). Demographics, survival rates and reasons for revision were evaluated and compared.

Results

In total, 346 (1.5%) implants had a Delta-on-Forte coupling (mean follow-up: 6.4 years). In total, 1163 (5%) THAs had a Forte-on-Delta articulation (mean follow-up: 8.2 years). Delta-on-Delta surfaces were implanted in 21,874 (93.5%) hips (mean follow-up: 3.9 years). Mixed material combinations were implanted between 2003 and 2007. The survival rates of the three cohorts were similar and were higher than 95% at 10 years. In Forte-on-Delta group, four liners failed (0.3% of the implants), whereas ceramic fractures occurred in 15 cases (0.1%) in Delta-on-Delta couplings (3 heads and 12 liners). Considering ceramic fracture as endpoint, there was no significant difference between the three survival rates.

Conclusions

Mixed ceramic bearing configurations from the same manufacturer in primary THA showed mid-to-longterm dependable outcomes, not inferior to the most recent like-on-like ceramic bearings. No additional risks of ceramic fractures were evident. Thus, closer follow-ups are not required.

中文翻译：

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初次全髋关节置换术中的混合陶瓷组合可确保中长期疗效。

介绍

陶瓷陶瓷耦合被证明是主要的全髋关节置换术（THA）的可靠轴承，具有长期的显着效果。广泛描述了类似结构。相反，对来自同一制造商的复式三角洲或复式三角洲的混合材料组合的研究很少。特别是，尚不清楚混合陶瓷组合是否更容易发生陶瓷破裂的风险。因此，进行了一项登记研究以研究混合陶瓷组合的长期存活率和原因。还进行了与Delta-on-Delta耦合的比较。

材料和方法

向区域关节置换注册处RIPO询问了三组陶瓷轴承（缸套：Forte Delta，Forte Delta，Delta Delta）。人口统计学，生存率和修订原因进行了评估和比较。

结果

总共有346个（1.5％）植入物具有Delta-on-Forte耦合（平均随访时间：6.4年）。共有1163（5％）的THA进行了三角洲复式手术（平均随访时间：8.2年）。三角洲表面植入了21,874（93.5％）髋关节中（平均随访时间：3.9年）。在2003年至2007年之间植入了混合材料组合。这三个队列的生存率相似，并且在10年时高于95％。在“三角洲复健”组中，有四个衬管破裂（占植入物的0.3％），而在“三角洲-三角洲”连接器（3个头部和12个衬管）中有15例（0.1％）发生了陶瓷骨折。以陶瓷骨折为终点，这三个存活率之间没有显着差异。

结论

同一制造商在THA中的混合陶瓷轴承配置显示了中长期可信赖的结果，并不逊色于最新的同类陶瓷轴承。没有明显的陶瓷破裂风险。因此，不需要更紧密的跟进。