Trauma Department, Hannover Medical School, Hannover, Germany.
Int J Med Robot. 2013 Dec;9(4):480-5. doi: 10.1002/rcs.1519. Epub 2013 Jul 3.
Reversed shoulder arthroplasty is an alternative to total shoulder arthroplasty for various indications. The long-term results depend on stable bone fixation, and correct positioning of the glenoid component. The potential contribution of image guidance for reversed shoulder arthroplasty procedures was tested in vitro.
27 positioning procedures (15 navigated, 12 non-navigated) of the glenoid baseplate in reverse shoulder arthroplasty were performed by a single experienced orthopaedic surgeon. A Kirschner wire was placed freehand or with the use of a navigated drill guide. For the navigated procedures, a flat detector 3D C-arm with navigation system was used. The Kirschner wire was to be inserted 12 mm from the inferior glenoid, with an inferior tilt of 10° and centrally in the axial scapular axis. The insertion point in the glenoid as well as the position of the K-wire in the axial and sagittal planes were measured. For statistical analysis, t-tests were performed with a significance level of 0.05.
The inferior glenoid drilling distance was 14.1 ± 3.4 mm for conventional placement and 15.1 ± 3.4 mm for the navigated procedure (P = 0.19). The inferior tilt showed no significant difference between the two methods (conventional 7.4 ± 5.2°, navigated 7.7 ± 4.9°, P = 0.63). The glenoid version in the axial plane showed significantly higher accuracy for the navigated procedure, with a mean deviation of 1.6 ±4.5° for the navigated procedure compared with 11.5 ± 6.5° for the conventional procedure(P = 0.004).
Accurate positioning of the glenoidal baseplate in the axial scapular plane can be improved using 3D C-arm navigation for reversed shoulder arthroplasty. However, computer navigation may not improve the inferior tilt of the component or the position in the inferior glenoid to avoid scapular notching. Nevertheless, further studies are required to confirm these findings in the clinical setup.
反向肩关节置换术是治疗各种适应症的全肩关节置换术的替代方法。长期结果取决于骨固定的稳定性和肩胛盂组件的正确定位。为了测试图像引导在反向肩关节置换手术中的潜在作用，我们进行了体外研究。
由一位经验丰富的骨科医生进行了 27 例反向肩关节置换术的肩胛盂基底部定位操作，其中 15 例为导航辅助，12 例为非导航辅助。使用徒手或导航钻头导向器放置克氏针。对于导航操作，使用带有导航系统的平板探测器 3D C 臂。克氏针应从肩胛盂下 12mm 处插入，下倾 10°，并位于肩胛轴的轴向。测量肩胛盂的插入点以及克氏针在矢状面和冠状面的位置。为了进行统计学分析，采用了 t 检验，显著性水平为 0.05。
常规方法下的肩胛盂钻孔距离为 14.1±3.4mm，导航辅助方法下为 15.1±3.4mm（P=0.19）。两种方法的下倾角无显著差异（常规方法 7.4±5.2°，导航辅助方法 7.7±4.9°，P=0.63）。轴向平面上的肩胛盂位置，导航辅助方法的准确性明显更高，导航辅助方法的平均偏差为 1.6±4.5°，而常规方法为 11.5±6.5°（P=0.004）。
在反向肩关节置换术中，使用 3D C 臂导航可以提高肩胛盂基底部在肩胛轴平面上的定位准确性。然而，计算机导航可能无法改善组件的下倾角或避免肩胛切迹的肩胛盂位置。然而，需要进一步的研究来确认这些发现是否适用于临床环境。
