Department of Orthopaedic Surgery, University Orthopaedic, Hand and Reconstructive Microsurgery Cluster, National University Health System (NUHS), 1E Kent Ridge Road, NUHS Tower Block, Level 11, Singapore, 119074, Singapore.
Department of Orthopaedic Surgery, Helwan University, Cairo, Egypt.
Knee Surg Sports Traumatol Arthrosc. 2018 Dec;26(12):3593-3600. doi: 10.1007/s00167-017-4795-0. Epub 2017 Nov 20.
To date, many radiographic parameters on patellar instability have their measurements taken statically, and have not been studied in various degrees of flexion according to the patellar tracking. There are also limited data regarding the use of these parameters in predicting recurrent patellar dislocation. The current study aims to review the radiographic parameters of the patellofemoral joint in different degrees of knee flexion and to correlate them with the presence of recurrent instability.
A 10-year retrospective study was conducted on all patients who had computed tomography patellar-tracking scan done for patellar instability when aged 18 years or younger. The computed tomography patellar-tracking scans were performed with the knee in extension, 10° flexion, and 20° flexion. The axial radiographic parameters were evaluated at the patellar equator, roman arch, and distal patellar pole. Sagittal and coronal parameters were noted. Radiographic parameters were then correlated with recurrent patellar instability.
The femoral sulcus angle and trochlear groove depth at the distal patellar pole in 10° knee flexion (p value 0.04 and 0.03, respectively) and patellar equator in 20° knee flexion (p value 0.02 and 0.03, respectively) had the most significant clinical correlations with recurrent instability on multivariate analysis. Other radiographic parameters found to have significant clinical correlation on univariate analysis include the patellar tilt angle, congruence angle, femoral sulcus angle, trochlear groove depth, and Wiberg's classification.
As per the knee dynamics, axial radiographic parameters had the most significant correlation with recurrent patellar instability when measured at the distal patellar pole in 10° knee flexion and at the patellar equator in 20° knee flexion. Future axial radiographic evaluation of patellofemoral instability should then be performed at these degrees of knee flexion and axial cuts. Trochlear dysplasia, as measured by the femoral sulcus angle and trochlear groove depth, was the most significant predictor of recurrent patellar instability in the skeletally immature. Wiberg's classification was also a novel factor found to have clinical correlation with patellofemoral instability.
III.
迄今为止，许多有关髌骨不稳定的影像学参数都是静态测量的，并且尚未根据髌骨轨迹在不同的膝关节弯曲度下进行研究。关于这些参数在预测复发性髌骨脱位中的应用，也仅有有限的数据。本研究旨在回顾不同膝关节弯曲度下髌股关节的影像学参数，并将其与复发性不稳定相关联。
对所有 18 岁或以下因髌骨不稳定而接受计算机断层扫描（CT）髌骨轨迹扫描的患者进行了一项为期 10 年的回顾性研究。CT 髌骨轨迹扫描在膝关节伸直、10°屈曲和 20°屈曲时进行。在髌骨赤道、罗马弓和髌骨远端极点处评估轴向影像学参数。记录矢状面和冠状面参数。然后将影像学参数与复发性髌骨不稳定相关联。
在 10°膝关节屈曲时，股骨滑车沟角和滑车沟深度在髌骨远端（p 值分别为 0.04 和 0.03）以及 20°膝关节屈曲时的髌骨赤道（p 值分别为 0.02 和 0.03）具有与复发性不稳定最显著的临床相关性。在单变量分析中发现与复发性不稳定具有显著临床相关性的其他影像学参数包括髌骨倾斜角、髌骨匹配角、股骨滑车沟角、滑车沟深度和 Wiberg 分级。
根据膝关节动力学，在 10°膝关节屈曲时测量髌骨远端和 20°膝关节屈曲时测量髌骨赤道的轴向影像学参数与复发性髌骨不稳定具有最显著的相关性。因此，未来应在这些膝关节弯曲度和轴向切面上进行髌股关节不稳定的轴向影像学评估。通过股骨滑车沟角和滑车沟深度测量的滑车发育不良是未成熟骨骼中复发性髌骨不稳定的最显著预测因素。Wiberg 分级也是与髌股关节不稳定具有临床相关性的一个新因素。
III 级。
