Orthopaedics, Cork University Hospital Group, Cork, Munster, Ireland
Orthopaedics, Cork University Hospital Group, Cork, Munster, Ireland.
BMJ Case Rep. 2021 Feb 4;14(2):e238333. doi: 10.1136/bcr-2020-238333.
A 74-year-old patient presented to the emergency department with acute atraumatic hip pain 9 years after her primary left total hip arthroplasty (THA). Plain radiographic imaging demonstrated lateralisation of the femoral head within the acetabular shell-indicating an issue with the polyethylene liner. The patient required revision of the acetabular component and the femoral head, as well as a new polyethylene liner. A detailed analysis of the components removed was performed by DePuy Synthes Engineering. Between 2009 and 2020, 8 publications have documented 52 cases of liner dissociation with the Pinnacle acetabular component and Marathon polyethylene liner. Various theories have been proposed in the literature as all of these components appear to fail in the same way, with shearing of the locking tabs in the polyethylene liner. In spite of a manufacturer analysis of the components, no root cause was identified as to why the polyethylene liner failed.
一位 74 岁的患者在初次左全髋关节置换术后 9 年因急性非创伤性髋关节疼痛就诊于急诊。平片影像学显示股骨头在髋臼壳内的外侧移位,提示聚乙烯衬垫出现问题。患者需要翻修髋臼部件和股骨头,并更换新的聚乙烯衬垫。对所取出的部件进行了详细的 DePuy Synthes 工程分析。2009 年至 2020 年间,有 8 篇文献记录了 Pinnacle 髋臼部件和 Marathon 聚乙烯衬垫发生 52 例衬垫分离的情况。文献中提出了各种理论,因为所有这些部件似乎都以相同的方式失效,即聚乙烯衬垫中的锁定凸耳发生剪切。尽管对部件进行了制造商分析,但仍未确定为什么聚乙烯衬垫会失效。