Department of Orthopaedic Surgery, Otto-von-Guericke University, Magdeburg, Germany.
University Orthopaedics, Hand and Reconstructive Microsurgery Cluster, National University Health System, Singapore.
J Arthroplasty. 2019 May;34(5):965-973. doi: 10.1016/j.arth.2018.12.040. Epub 2019 Jan 6.
There is a paucity of reports on osteolysis associated with tibial screw fixation in cementless total knee arthroplasty (TKA), and the pathophysiology is not clear. This study aimed to describe the pathology related to screw track osteolysis around the tibia in cementless TKA.
The study cohort comprised 100 revised cementless TKAs with tibial screw fixation. Screw track osteolysis and various screw angles were analyzed radiologically. Tissue samples from the joint capsule and the osteolytic cavity were investigated for metal/polyethylene wear. The type of tissue response was determined using immunohistochemistry. Retrieved tibial polyethylene inserts were analyzed for screw hole impression and mode of wear. Tissue metal content was measured by inductively coupled plasma optical emission spectrometry. Electrochemical reactions between the tibial tray and the cancellous screws were investigated.
Radiological analysis showed screw track osteolysis predominantly at the medial aspect of the tibial component, and the severity of osteolysis positively correlated with smaller medial proximal tibial screw angles. Osteolysis was associated with high titanium concentrations but not with polyethylene particles. An open circuit potential between the screw and the tibial base plate was measured. Necrosis, osteolytic cyst formation and macrophages, T and B cells, and dendritic cells were present.
The present study highlights the risk for screw track osteolysis in cementless TKA with screw fixation. Our data collectively suggest that titanium wear may contribute to screw track osteolysis in the cementless TKA design. The contribution of screw angles is difficult to prove.
在非骨水泥全膝关节置换术（TKA）中，胫骨螺钉固定相关的骨溶解现象报告较少，其病理生理学尚不清楚。本研究旨在描述非骨水泥 TKA 中胫骨螺钉固定相关的螺钉轨迹骨溶解的病理学。
研究队列包括 100 例经翻修的非骨水泥 TKA 患者，均行胫骨螺钉固定。对螺钉轨迹骨溶解和各种螺钉角度进行影像学分析。对关节囊和骨溶解腔的组织样本进行金属/聚乙烯磨损检查。采用免疫组织化学法确定组织反应类型。对取出的胫骨聚乙烯衬垫进行螺钉孔压痕和磨损模式分析。采用电感耦合等离子体发射光谱法测量组织金属含量。研究胫骨托与松质骨螺钉之间的电化学反应。
影像学分析显示，胫骨组件的内侧主要存在螺钉轨迹骨溶解，骨溶解的严重程度与较小的内侧近胫骨螺钉角度呈正相关。骨溶解与高钛浓度有关，但与聚乙烯颗粒无关。测量了螺钉与胫骨基底部之间的开路电位。存在坏死、溶骨性囊肿形成和巨噬细胞、T 细胞和 B 细胞以及树突状细胞。
本研究强调了非骨水泥 TKA 中螺钉固定存在螺钉轨迹骨溶解的风险。我们的数据提示，钛磨损可能导致非骨水泥 TKA 设计中出现螺钉轨迹骨溶解。螺钉角度的影响很难证明。
