Borsinger Tracy M, Chandi Sonia K, Belay Elshaday S, Chiu Yu-Fen, Gausden Elizabeth B, Sculco Thomas P, Westrich Geoffrey H
Adult Reconstruction and Joint Replacement, Hospital for Special Surgery, New York, New York; Department of Orthoapedic Surgery, University of Virginia, Charlottesville, Virginia.
Adult Reconstruction and Joint Replacement, Hospital for Special Surgery, New York, New York.
J Arthroplasty. 2024 Sep;39(9):2285-2288. doi: 10.1016/j.arth.2024.04.041. Epub 2024 Apr 18.
Identification of femoral component debonding in the work-up of painful total knee arthroplasty (TKA) often poses a diagnostic challenge. The purpose of this study was to compare the sensitivity and specificity of radiographs, computed tomography (CT), and magnetic resonance imaging (MRI) for identifying femoral component loosening with debonding at the time of revision of a primary TKA with a recalled polyethylene insert.
Using an institutional database, we identified all cases of revision TKA performed for this specific implant recall following a primary TKA between 2014 and 2022. Patients who had a preoperative radiograph, CT, and MRI were included (n = 77). Sensitivity, specificity, and positive and negative likelihood ratio (LR) for predicting loosening were compared among the imaging modalities, using the intraoperative evidence of implant loosening as the gold standard.
At the time of revision surgery, the femoral component was noted to have aseptic loosening with debonding in 46 of the 77 (60%) of the TKAs. There were no significant differences in demographics in the cohort with femoral debonding compared to those with well-fixed implants. The CT demonstrated a sensitivity of 28% and a specificity of 97%, while the MRI demonstrated a sensitivity of 37% and a specificity of 94% for detecting femoral loosening due to debonding. Both CT and MRI demonstrated poor negative LRs for femoral loosening (LR 0.7).
In this series of revision TKAs for a specific recalled component, neither CT nor MRI accurately diagnosed femoral component debonding. For patients who have this implant, it is imperative to interrogate the implant-cement interface intraoperatively and prepare for full revision surgery as well as marked bone loss secondary to osteolysis.
在疼痛性全膝关节置换术（TKA）的检查过程中，识别股骨组件脱粘通常是一项诊断挑战。本研究的目的是比较X线片、计算机断层扫描（CT）和磁共振成像（MRI）在翻修初次TKA且使用召回的聚乙烯内衬时识别伴有脱粘的股骨组件松动的敏感性和特异性。
利用机构数据库，我们识别了2014年至2022年间初次TKA后因该特定植入物召回而进行的所有翻修TKA病例。纳入术前有X线片、CT和MRI检查的患者（n = 77）。以术中植入物松动的证据作为金标准，比较各成像方式预测松动的敏感性、特异性以及阳性和阴性似然比（LR）。
在翻修手术时，77例TKA中有46例（60%）的股骨组件存在无菌性松动并伴有脱粘。与植入物固定良好的患者相比，股骨脱粘患者队列中的人口统计学特征无显著差异。CT检测因脱粘导致的股骨松动的敏感性为28%，特异性为97%，而MRI的敏感性为37%，特异性为94%。CT和MRI检测股骨松动的阴性似然比均较差（LR 0.7）。
在这一系列针对特定召回组件的翻修TKA中，CT和MRI均不能准确诊断股骨组件脱粘。对于植入这种植入物的患者，术中必须检查植入物与骨水泥的界面，并为全翻修手术以及继发于骨溶解的明显骨丢失做好准备。
