Department of Clinical Research, University of Basel, 4051, Basel, Switzerland.
Department of Orthopaedic Surgery and Traumatology, Kantonsspital Baselland (Bruderholz, Liestal, Laufen), 4101, Bruderholz, Switzerland.
BMC Musculoskelet Disord. 2021 Nov 30;22(1):1003. doi: 10.1186/s12891-021-04898-y.
With the Persona® knee system a new polyethylene formulation incorporating vitamin-E which aims to reduce oxidation and maintain wear resistance was introduced. Although in-vitro studies have demonstrated positive effects of the vitamin-E antioxidants on UHMWPE, no retrieval study has looked at polyethylene damage of this system yet. It was the aim to investigate the in-vivo performance of this new design, by comparing it with its predecessor in retrieval analysis.
15 NexGen® and 8 Persona® fixed-bearing implants from the same manufacturer (Zimmer Biomet) were retrieved from two knee revision centres. For retrieval analysis, a macroscopic analysis of polyethylene using a peer-reviewed damage grading method was used (Hood-score). The roughness of all articulating metal components was measured using a contact profilometer. The reason(s) for TKA revision were recorded. Statistical analyses (t-test) were performed to investigate differences between the two designs.
The mean Hood score for Persona® inserts was 109.3 and for NexGen® 115.1 without significant differences between the two designs. Results from the profilometer revealed that Persona® and NexGen® femoral implants showed an identical mean surface roughness of 0.14 μm. The Persona® tibial tray showed a significantly smoother surface (0.06 μm) compared to the NexGen® (0.2 μm; p < 0.001). Both Hood score and surface roughness were influenced by the reasons for revision (p < 0.01).
The bonding of the antioxidant vitamin-E to the PE chain used in the novel Persona® knee system does not reduce in-vivo surface damage compared to highly crosslinked PE without supplemented vitamin-E used in its predecessor knee system NexGen®. However, the Persona® titanium alloy tibial tray showed a significantly smoother surface in comparison to the NexGen® titanium alloy tibial tray. This study provides first retrieval findings of a novel TKA design and may help to understand how the new Persona® anatomic knee system performs in vivo.
随着 Persona®膝关节系统的出现，一种新的含维生素 E 的聚乙烯配方被引入，旨在减少氧化并保持耐磨性。尽管体外研究已经证明了维生素 E 抗氧化剂对超高分子量聚乙烯的积极影响，但尚未有检索研究关注该系统的聚乙烯损伤情况。本研究旨在通过与同一家制造商（Zimmer Biomet）的前代 NexGen®固定轴承植入物进行检索分析，来研究这种新设计的体内性能。
从两个膝关节翻修中心取出 15 个 NexGen®和 8 个 Persona®固定轴承植入物（均来自 Zimmer Biomet）。为了进行检索分析，使用经过同行评审的损伤分级方法（Hood 评分）对聚乙烯进行了宏观分析。使用接触式轮廓仪测量所有关节金属部件的粗糙度。记录 TKA 翻修的原因。采用 t 检验进行统计分析，以研究两种设计之间的差异。
Persona®植入物的平均 Hood 评分为 109.3，NexGen®植入物的平均 Hood 评分为 115.1，两种设计之间无显著差异。轮廓仪的结果表明，Persona®和 NexGen®股骨植入物的平均表面粗糙度相同，均为 0.14μm。与 NexGen®（0.2μm；p<0.001）相比，Persona®胫骨托的表面明显更光滑（0.06μm）。Hood 评分和表面粗糙度均受翻修原因的影响（p<0.01）。
与在其前代膝关节系统 NexGen®中使用的未添加维生素 E 的高度交联聚乙烯相比，新型 Persona®膝关节系统中使用的含抗氧化维生素 E 的聚乙烯链的体内表面损伤并没有减少。然而，与 NexGen®钛合金胫骨托相比，Persona®钛合金胫骨托的表面明显更光滑。本研究提供了一种新型 TKA 设计的首次检索结果，有助于了解新型 Persona®解剖型膝关节系统在体内的性能。
