Unit of Orthopaedic Surgery, Department of Public Health, School of Medicine, Federico II University, Naples, Italy.
Jt Dis Relat Surg. 2024 Aug 14;35(3):473-482. doi: 10.52312/jdrs.2024.1591.
The study focused on the ability to predict the need and size of femoral and tibial augmentation using standard two-dimensional (2D) templates and models created with three-dimensional (3D) printing in surgical planning.
This observational cohort study included 28 consecutive patients (22 females, 6 males; mean age: 71±7.3 years; range, 54 to 82 years) with periprosthetic joint infection recruited between March 2021 and September 2023 undergoing revision total knee arthroplasty revision (TKA). Standard planning was made using calibrated X-ray images. The 3D planning started with computed tomography scans to generate a 3D template of the distal femur and proximal tibia. The model was exported to a 3D printer to produce a patient-specific phantom. The surgery was then simulated on the 3D phantom using revision knee arthroplasty instrumentation to evaluate the appropriate augmentation to use until a correct alignment was obtained.
Three-dimensional planning predicted the need for femoral and tibial augments in 22 (78.6%) cases at both the tibial and femoral components, while 2D planning correctly predicted the need for augmentation in 17 (60.7%) for the tibial side and 18 (64.3%) for the femoral side. The Cohen's kappa demonstrated a significant agreement between the 3D planning for the femoral metal block and the intraoperative requirement (kappa=0.553), whereas 2D planning showed only nonsignificant poor agreement (kappa=0.083). In contrast, the agreement between 2D or 3D preoperative planning for tibial augment and the intraoperative requirement was nonsignificant (kappa=0.130 and kappa=0.158, respectively). On the femoral side, 2D planning showed only a fair nonsignificant correlation (r=0.35, p=0.069), whereas 3D planning exhibited substantial agreement with the actual thickness of the implanted augment (r=0.65, p<0.001). On the tibial side, 3D and 2D planning showed substantial agreement with the actual size of implanted augments (3D planning, r=0.73, p<0.001; 2D planning, r=0.69, p<0.001).
Prediction based on 3D computed tomography segmentation showed significant agreement with the intraoperative need for augmentations in revision TKA. The results suggest that planning with 3D printed models represents a stronger aid in this kind of surgery rather than standard 2D planning, providing greater accuracy in the prediction of the required augmentation in revision TKA.
本研究专注于使用标准二维（2D）模板和三维（3D）打印创建的模型，在手术规划中预测股骨和胫骨增强的需求和大小的能力。
本观察性队列研究纳入了 2021 年 3 月至 2023 年 9 月期间接受翻修全膝关节置换术（TKA）的 28 例连续患者（22 名女性，6 名男性；平均年龄：71±7.3 岁；范围 54 岁至 82 岁）。使用校准 X 射线图像进行标准规划。3D 规划始于计算机断层扫描，以生成远端股骨和近端胫骨的 3D 模板。将模型导出到 3D 打印机以生成患者特定的模型。然后，使用翻修膝关节置换器械在 3D 模型上模拟手术，以评估直到获得正确对线所需的适当增强。
在胫骨和股骨部件上，3D 规划预测 22 例（78.6%）需要股骨和胫骨增强，而 2D 规划正确预测胫骨侧需要增强的有 17 例（60.7%），股骨侧需要增强的有 18 例（64.3%）。Cohen's kappa 显示 3D 规划与术中需要的股骨金属块之间存在显著一致（kappa=0.553），而 2D 规划仅显示无统计学意义的一致性较差（kappa=0.083）。相比之下，2D 或 3D 术前规划胫骨增强与术中需求之间的一致性无统计学意义（kappa=0.130 和 kappa=0.158）。在股骨侧，2D 规划仅显示出适度的无统计学意义的相关性（r=0.35，p=0.069），而 3D 规划与植入增强物的实际厚度显示出显著一致（r=0.65，p<0.001）。在胫骨侧，3D 和 2D 规划与植入增强物的实际尺寸显示出显著一致（3D 规划，r=0.73，p<0.001；2D 规划，r=0.69，p<0.001）。
基于 3D 计算机断层扫描分割的预测与翻修 TKA 术中增强的需求具有显著一致性。结果表明，使用 3D 打印模型进行规划在这种手术中是一种更强有力的辅助手段，而不是标准的 2D 规划，在预测翻修 TKA 中所需的增强方面提供了更高的准确性。
