Chen Yurou, Yu Fan, Rong Fanzhuang, Lv Furong, Lv Fajin, Li Jia
Department of Radiology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
Shenzhen Angell Technology Co. Ltd., Shenzhen, China.
Insights Imaging. 2025 Jan 2;16(1):1. doi: 10.1186/s13244-024-01883-6.
To propose a reliable and standard 3D assessment method to analyze the effect of weight-bearing (WB) status on the location of patella and clarify the diagnostic performance of 3D parameters for recurrent patellar dislocation (RPD) in WB and non-weight-bearing (NWB) conditions.
Sixty-five knees of RPD patients and 99 knees of controls were included. Eight landmarks, two lines and a coordinate system were defined on 3D bone models of knees based on weight-bearing CT and non-weight-bearing CT. The shift and tilt of patella in three orthogonal axes (X, Y, Z, X, Y, Z) were evaluated.
X and Y were significantly higher, Z, X and Y were significantly lower in WB condition than NWB condition (p < 0.001, p < 0.001, p = 0.001, p = 0.002, p = 0.010). In both WB and NWB conditions, X, Y and Z were significantly higher, and X was significantly lower in the RPD group than the control group (WB/NWB: p < 0.001/p = 0.002, p < 0.001/p = 0.001, p < 0.001/p < 0.001, p < 0.001/p = 0.009). In WB condition, Z and Y were significantly higher in the RPD group than the control group (p = 0.011, p < 0.001). Z had the best diagnostic performance for RPD in both WB and NWB conditions, with AUC of 0.887 (95% CI: 0.828, 0.946) and 0.885 (95% CI: 0.822, 0.947), respectively.
The 3D measurement method reliably and comprehensively reflected the relative spatial position relationship of the patellofemoral joint. It can be applied to the 3D preoperative planning of patellofemoral procedures. In addition, patellofemoral evaluation under the WB condition was essential to detect subtle underlying risk factors for RPD, with axial lateral patellar tilt being the best predictor.
This 3D measurement method under weight-bearing conditions contributes to comprehensively describing the relative spatial position of the patellofemoral joint in a standardized way and can be applied to preoperative evaluation for recurrent patellar dislocation.
Patellofemoral alignment is a 3D problem, and the accuracy of 2D parameters has been questioned. 3D measurement was reliable and comprehensively reflected relative spatial relationships of the patellofemoral joint. 3D measurements under weight-bearing condition help preoperative evaluation for RPD.
提出一种可靠且标准的三维评估方法，以分析负重（WB）状态对髌骨位置的影响，并阐明三维参数在负重和非负重（NWB）条件下对复发性髌骨脱位（RPD）的诊断性能。
纳入65例RPD患者的膝关节和99例对照者的膝关节。基于负重CT和非负重CT在膝关节的三维骨骼模型上定义了8个标志点、两条线和一个坐标系。评估髌骨在三个正交轴（X、Y、Z、X、Y、Z）上的移位和倾斜情况。
与非负重状态相比，负重状态下X和Y显著更高，Z、X和Y显著更低（p < 0.001，p < 0.001，p = 0.001，p = 0.002，p = 0.010）。在负重和非负重条件下，RPD组的X、Y和Z均显著更高，且X显著低于对照组（负重/非负重：p < 0.001/p = 0.002，p < 0.001/p = 0.001，p < 0.001/p < 0.001，p < 0.001/p = 0.009）。在负重条件下，RPD组的Z和Y显著高于对照组（p = 0.011，p < 0.001）。在负重和非负重条件下，Z对RPD的诊断性能最佳，其曲线下面积（AUC）分别为0.887（95%可信区间：0.828，0.946）和0.885（95%可信区间：0.822，0.947）。
三维测量方法可靠且全面地反映了髌股关节的相对空间位置关系。它可应用于髌股手术的三维术前规划。此外，负重条件下的髌股评估对于检测RPD的潜在细微危险因素至关重要，其中髌骨轴向外侧倾斜是最佳预测指标。
这种负重条件下的三维测量方法有助于以标准化方式全面描述髌股关节的相对空间位置，并可应用于复发性髌骨脱位的术前评估。
髌股对线是一个三维问题，二维参数的准确性受到质疑。三维测量可靠且全面地反映了髌股关节的相对空间关系。负重条件下的三维测量有助于RPD的术前评估。
