Shoulder Center, Hirslanden Clinique la Colline, Geneva, Switzerland; Division of Orthopaedics and Trauma Surgery, Geneva University Hospitals, Geneva, Switzerland.
Department of Radiology, Royal North Shore Hospital, Sydney, NSW, Australia.
J Shoulder Elbow Surg. 2018 Oct;27(10):1809-1815. doi: 10.1016/j.jse.2018.03.016. Epub 2018 May 31.
Most glenoid version measurement methods have been validated on 3-dimensionally corrected axial computed tomography (CT) slices at the mid glenoid. Variability of the vault according to slice height and angulation has not yet been studied and is crucial for proper surgical implant positioning. The aim of this study was to analyze the variation of the glenoid vault compared with the Friedman angle according to different CT slice heights and angulations. The hypothesis was that the Friedman angle would show less variability.
Sixty shoulder CT scans were retrieved from a hospital imaging database and were reconstructed in the plane of the scapula. Seven axial slices of different heights and coronal angulations were selected, and measurements were carried out by 3 observers.
Mid-glenoid mean version was -8.0° (±4.9°; range, -19.6° to +7.0°) and -2.1° (±4.7°; range, -13.0° to +10.3°) using the vault method and Friedman angle, respectively. For both methods, decreasing slice height or angulation did not significantly alter version. Increasing slice height or angulation significantly increased anteversion for the vault method (P < .001). Both interobserver reliability and intraobserver reliability were significantly higher using the Friedman angle.
Version at the mid and lower glenoid is similar using either method. The vault method shows less reliability and more variability according to slice height or angulation. Yet, as it significantly differs from the Friedman angle, it should still be used in situations where maximum bone purchase is sought with glenoid implants. For any other situation, the Friedman angle remains the method of choice.
大多数肩胛盂版本测量方法已在肩胛盂中部的三维校正轴向计算机断层扫描（CT）切片上得到验证。根据层面高度和角度的穹顶变化尚未得到研究，这对于正确的手术植入物定位至关重要。本研究的目的是分析根据不同 CT 切片高度和角度，与 Friedman 角相比，肩胛盂穹顶的变化。假设是 Friedman 角的变化会更小。
从医院的图像数据库中检索了 60 例肩部 CT 扫描，并在肩胛骨平面上进行重建。选择了 7 个不同高度和冠状角度的轴向切片，并由 3 名观察者进行测量。
使用穹顶法和 Friedman 角测量的肩胛盂中部平均版本分别为-8.0°（±4.9°；范围，-19.6°至+7.0°）和-2.1°（±4.7°；范围，-13.0°至+10.3°）。对于这两种方法，降低切片高度或角度都不会显著改变版本。增加切片高度或角度会显著增加穹顶法的前倾角（P < .001）。使用 Friedman 角时，观察者间可靠性和观察者内可靠性均显著更高。
使用这两种方法，肩胛盂中部和下部的版本相似。穹顶法的可靠性较低，根据切片高度或角度的变化较大。然而，由于它与 Friedman 角显著不同，因此仍应在寻求与肩胛盂植入物最大骨接触的情况下使用。对于任何其他情况，Friedman 角仍然是首选方法。
