Department of Orthopaedic Surgery, HELIOS ENDO-Klinik Hamburg, Hamburg, Germany.
Department of Orthopaedics and Traumatology, Ankara Yildirim Beyazit Universitesi Tip Fakultesi, Ankara, Turkey.
Z Orthop Unfall. 2023 Aug;161(4):429-433. doi: 10.1055/a-1685-0955. Epub 2021 Dec 8.
Aseptic loosening (AL) is among the most important causes of failure after total knee arthroplasty (TKA). However, while there are numerous underlying causes of AL, the morphometry of the distal femur and intramedullary canal has not been sufficiently demonstrated. This study aimed to show the interobserver and intraobserver reliability and validity of the Citak classification, which has been recently defined according to the morphometry of the distal femur and provides a risk factor definition for AL.
A total of 200 patients whose standardized anteroposterior (AP) and lateral images of the knee joint were obtained between October 2019 and April 2020 were retrospectively evaluated in this study. Patients with a history of extra-articular deformity and knee surgery were excluded from the study. For AL, morphologies of the distal femur were identified by two observers using the new radiological classification system of the distal femur. Mean pairwise Cronbach's alpha coefficient was used to assess the intra- and interobserver agreement of the classification.
There was excellent interobserver agreement for the 20 cm proximal and 2 cm proximal to the lateral joint line (PLJL) and adductor tubercle (PAD), respectively. The mean Cronbach's alpha coefficient was 0.96 (range 0.764-0.944) for the PAD and 0.98 (range 0.734-0.929) for the PLJL. There was also an excellent intraobserver agreement, with 93% average pairwise percent agreement for the index group and 95.5% average pairwise percent agreement for the anatomical classification group.
The level of inter- and intraobserver agreement for the morphology of the distal femur was excellent in the new radiological classification system, which was shown to be beneficial in the planning of revision knee arthroplasty for AL. However, there is a need for further studies in order to make a correlation of the classification with specific intraoperative findings.
无菌性松动（AL）是全膝关节置换术（TKA）后失败的重要原因之一。然而，虽然 AL 有许多潜在原因，但股骨远端和髓内管的形态并未得到充分证明。本研究旨在展示最近根据股骨远端形态定义的 Citak 分类的观察者间和观察者内可靠性和有效性，并为 AL 提供风险因素定义。
本研究回顾性评估了 2019 年 10 月至 2020 年 4 月期间获得的膝关节标准前后位（AP）和侧位图像的 200 例患者。排除有关节外畸形和膝关节手术史的患者。对于 AL，两名观察者使用新的股骨远端放射学分类系统识别股骨远端的形态。使用平均配对 Cronbach's alpha 系数评估分类的观察者内和观察者间一致性。
在 20cm 近端和外侧关节线（PLJL）近端 2cm 处，观察者间的评估具有极好的一致性。平均 Cronbach's alpha 系数分别为 0.96（范围为 0.764-0.944）和 0.98（范围为 0.734-0.929）。观察者内的一致性也很好，指数组的平均配对百分比一致性为 93%，解剖分类组的平均配对百分比一致性为 95.5%。
新的放射学分类系统中股骨远端形态的观察者间和观察者内一致性水平很高，这对计划 AL 翻修膝关节置换术非常有益。然而，需要进一步的研究来使分类与特定的术中发现相关联。
