Hiranaka Takafumi, Furuhashi Ryosuke, Takashiba Kenichiro, Kodama Takao, Michishita Kazuhiko, Inui Hiroshi, Togashi Eita
Department of Orthopaedic Surgery and Joint Surgery Centre, Takatsuki General Hospital, 1-3-13 Kosobe, Takatski City, Osaka, 569-1192, Japan.
Department of Orthopaedic Surgery and Joint Surgery Centre, Takatsuki General Hospital, 1-3-13, Kosobe-Cho, Takatsuki City, Osaka, 561-1115, Japan.
Knee Surg Relat Res. 2022 Mar 14;34(1):13. doi: 10.1186/s43019-022-00140-8.
Indication for mobile-bearing partial knee replacement (PKR) is made on the basis of a radiological decision aid. This study aimed to reveal the inter-rater reproducibility and accuracy of the decision aid when used by experienced surgeons.
Anonymised radiographic image sets (anteroposterior, lateral, varus/valgus stress in 20° knee flexion, and skyline views) from 20 consecutive patients who underwent knee replacement were assessed by 12 experienced surgeons. Agreements of each section and accuracy were compared by intra-operative inspection of the status of the anterior cruciate ligament (ACL) and medial and lateral cartilage according to the protocol of Radiographic Assessment for Medial Oxford PKR. Fleiss' kappa (κ) values were used as a statistical measure.
Full-thickness medial cartilage had the best agreement between the surgeons (κ = 94.7%) and best accuracy (94.2%). Although functioning ACL (90.8%), intact cartilage (91.7%) and full-thickness lateral cartilage defects (86.1%) were accurately diagnosed, diagnoses of deficient ACL (up to 42.5%) and partial-thickness lateral cartilage defects (11.7%) were poor; they were sometimes misdiagnosed as being intact. Moreover, agreement of lateral and valgus stress radiographs regarding intact MCL function, as well as the overall decision, was considered to be inadequate (κ = 0.47, 0.58 and 0.51, respectively).
Although the radiological aid is useful for selection of patients who are likely to be suitable for PKR, surgeons should still carefully assess the lateral weight-bearing area for partial-thickness loss and deficiency of the ACL because they were sometimes overlooked by surgeons using radiographs. MRI will be helpful to improve the accuracy of determination of Oxford PKR indication.
活动平台部分膝关节置换术（PKR）的适应症是基于一种放射学决策辅助工具来确定的。本研究旨在揭示经验丰富的外科医生使用该决策辅助工具时的评分者间再现性和准确性。
12位经验丰富的外科医生对20例连续接受膝关节置换术患者的匿名放射影像集（前后位、侧位、膝关节屈曲20°时的内翻/外翻应力位以及髌股关节切线位）进行评估。根据内侧牛津PKR的放射学评估方案，通过术中检查前交叉韧带（ACL）以及内侧和外侧软骨的状况，比较各部分的一致性和准确性。采用Fleiss' kappa（κ）值作为统计指标。
外科医生之间对于全层内侧软骨的一致性最佳（κ = 94.7%），准确性也最高（94.2%）。虽然功能正常的ACL（90.8%）、完整的软骨（91.7%）和全层外侧软骨缺损（86.1%）能够被准确诊断，但ACL缺失（高达42.5%）和外侧软骨部分厚度缺损（11.7%）的诊断效果较差；它们有时会被误诊为完整。此外，关于内侧副韧带（MCL）功能完整以及整体决策的外侧和外翻应力位X线片的一致性被认为不足（κ分别为0.47、0.58和0.51）。
尽管放射学辅助工具对于选择可能适合PKR的患者很有用，但外科医生仍应仔细评估外侧负重区域的软骨部分厚度损失和ACL缺失情况，因为使用X线片时这些情况有时会被外科医生忽视。磁共振成像（MRI）将有助于提高牛津PKR适应症判定的准确性。
