Department of Surgery, London Health Sciences Centre - University Hospital, Division of Orthopaedic Surgery, ON, Canada.
Surgical Innovation Program, Lawson Health Research Institute, London, ON, Canada.
Hip Int. 2024 May;34(3):363-371. doi: 10.1177/11207000231199941. Epub 2023 Oct 2.
Corrosion at the head-neck junction of femoral stems is a rare complication of total hip arthroplasty (THA) with manifestations ranging from subclinical wear to failure. Prior studies have identified a single femoral component design with an increased propensity for catastrophic trunnion failure. The purpose of the present study was to quantify trunnion damage of this femoral component retrieved from patients undergoing revision THA for non-trunnionosis indications.
24 femoral components from a single manufacturer were identified for study inclusion. Each prosthesis underwent stereomicroscopic inspection. Corrosion and fretting scores were assigned per the Goldberg criteria to quadrants of the trunnion. Material loss was calculated based on cone angles across trunnion quadrants. This was carried out using a coordinate measuring machine that digitised each trunnion surface. Stems were compared to a series of femoral stems with the same trunnion design.
20 of the 24 (83%) trunnions demonstrated corrosion, all 24 trunnions demonstrated fretting. Corrosion scores did not statistically differ with respect to trunnion zone ( = 0.53), while fretting scores were higher in the inferior compared to the superior zones ( 0.001). There was no significant difference in cone angles assessing material loss between stems ( = 0.25).
Evidence of trunnion damage was observed in each stem retrieved for non-trunnionosis revision. Fretting occurred more frequently about the inferior quadrants. However, digitised trunnion shapes were similar between compared stems exhibiting no material loss. Therefore, it is possible that previous reports of trunnion failures for this implant are not a systemic issue, and that further investigation is required.
股骨柄头颈交界处的腐蚀是全髋关节置换术（THA）的一种罕见并发症，其表现从亚临床磨损到失败不等。先前的研究已经确定了一种股骨部件设计，其灾难性的轴头失败倾向增加。本研究的目的是量化从因非轴头病变而接受翻修 THA 的患者中取出的这种股骨部件的轴头损伤。
确定了来自单一制造商的 24 个股骨部件进行研究。每个假体都进行了立体显微镜检查。根据 Goldberg 标准，对轴头的象限进行腐蚀和微动评分。根据穿过轴头象限的锥形角度计算材料损失。这是使用坐标测量机完成的，该坐标测量机对每个轴头表面进行数字化。将这些股骨柄与具有相同轴头设计的一系列股骨柄进行比较。
24 个轴头中有 20 个（83%）显示腐蚀，所有 24 个轴头均显示微动。腐蚀评分与轴头区域没有统计学差异（ = 0.53），而下部区域的微动评分高于上部区域（ 0.001）。评估材料损失的锥形角度之间的 stems 没有显著差异（ = 0.25）。
在因非轴头病变而翻修的每个股骨柄中都观察到轴头损伤的证据。微动更频繁地发生在下部象限。然而，比较的股骨柄之间的数字化轴头形状相似，没有材料损失。因此，该植入物的先前轴头故障报告可能不是系统性问题，需要进一步调查。
