Nakasone Satoshi, Takaesu Mika, Ishihara Masato, Onaga Masamichi, Igei Takahiro, Miyata Yoshihide, Nishida Kotaro
Department of Orthopedic Surgery, Graduate School of Medicine, University of the Ryukyus, Okinawa, Japan.
Department of Orthopedic Surgery, Chubu Tokushukai Hospital, Okinawa, Japan.
Arthroplast Today. 2022 May 23;16:46-52. doi: 10.1016/j.artd.2022.04.004. eCollection 2022 Aug.
Accurate cup placement during total hip arthroplasty (THA) is difficult because the intraoperative pelvic position changes even in supine patient position. We developed a device known as HipPointer; it corrects pelvic rotation and creates a functional pelvic plane as a reference. The aim of this study was to determine the device placement accuracy and investigate causes of error.
HipPointer was used for cup placement in 353 hips of 308 patients who underwent direct-anterior-approach THA in supine position. The mean age at surgery and body mass index were 63.9 (17-90) years and 24.9 (16.6-42.0) kg/m, respectively. The mean observation period was 40.5 (12-73) months. To investigate the accuracy of HipPointer, preoperative planning and postoperative cup placement angles relative to the functional pelvic plane were evaluated using a three-dimensional analysis software, and absolute errors were determined.
The means ± standard deviations of radiographic inclination (RI) and radiographic anteversion (RA) were 40.2 ± 3.0° and 15.8 ± 3.6°, respectively. The absolute errors of RI and RA were 2.2 ± 2.0° and 2.7 ± 2.3°, respectively. The ratio of the cup placement angle for which both RI and RA are ≤10° in the target zone was 99% (350/353 hips), and the ratio of the absolute errors for which both RI and RA are ≤5° was 80.4% (284/353 hips).
HipPointer is simple in structure, easy to use, and useful for direct-anterior-approach THA in supine position. It provides good cup placement accuracy.
在全髋关节置换术（THA）中，即使患者处于仰卧位，术中骨盆位置仍会发生变化，因此准确放置髋臼杯具有一定难度。我们研发了一种名为HipPointer的装置；它可纠正骨盆旋转并创建一个功能性骨盆平面作为参考。本研究的目的是确定该装置的放置准确性并调查误差原因。
在308例接受仰卧位直接前路THA的患者的353个髋关节中使用HipPointer进行髋臼杯放置。手术时的平均年龄和体重指数分别为63.9（17 - 90）岁和24.9（16.6 - 42.0）kg/m²。平均观察期为40.5（12 - 73）个月。为研究HipPointer的准确性，使用三维分析软件评估术前规划和术后髋臼杯相对于功能性骨盆平面的放置角度，并确定绝对误差。
影像学倾斜度（RI）和影像学前倾角（RA）的平均值±标准差分别为40.2±3.0°和15.8±3.6°。RI和RA的绝对误差分别为2.2±2.0°和2.7±2.3°。目标区域中RI和RA均≤10°的髋臼杯放置角度的比例为99%（350/353个髋关节），RI和RA均≤5°的绝对误差的比例为80.4%（284/353个髋关节）。
HipPointer结构简单，易于使用，对于仰卧位直接前路THA很有用。它能提供良好的髋臼杯放置准确性。
