Department of Orthopaedic Surgery, Asahikawa Medical University, Asahikawa, Japan.
J Arthroplasty. 2020 Jan;35(1):172-177. doi: 10.1016/j.arth.2019.08.044. Epub 2019 Aug 27.
Malposition of the acetabular component during total hip arthroplasty (THA) is associated with increased risk of dislocation, reduced range of motion, and accelerated wear. The purpose of this study is to compare cup positioning with a portable, accelerometer-based hip navigation system and conventional surgical technique.
In a prospective, randomized, clinical study, cups were implanted with a portable, accelerometer-based hip navigation system (navigation group; n = 55) or conventional technique (conventional group; n = 55). THA was conducted in the lateral position and through posterior approach. The cup position was determined postoperatively on pelvic radiograph and computed tomography scans.
An average cup abduction of 39.2° ± 4.6° (range, 27° to 50°) and an average cup anteversion of 14.6° ± 6.1° (range, 1° to 27.5°) were found in the navigation group, and an average cup abduction of 42.9° ± 8.0° (range, 23° to 73°) and an average cup anteversion of 11.6° ± 7.7° (range, -12.1° to 25°) in the conventional group. A smaller variation in the navigation group was indicated for cup abduction (P = .001). The deviations from the target cup position were significantly lower in the navigation group (P = .001, .016). While only 37 of 55 cups in the conventional group were inside the Lewinnek safe zone, 51 of 55 cups in the navigation group were placed inside this safe zone (P = .006). The navigation procedure took a mean of 10 minutes longer than the conventional technique.
Use of the portable, accelerometer-based hip navigation system can improve cup positioning in THA.
全髋关节置换术（THA）中髋臼部件位置不良与脱位风险增加、活动范围减小和加速磨损有关。本研究旨在比较使用便携式、基于加速度计的髋关节导航系统和传统手术技术进行杯置位的效果。
在一项前瞻性、随机、临床研究中，使用便携式、基于加速度计的髋关节导航系统（导航组；n=55）或传统技术（常规组；n=55）植入髋臼杯。THA 采用侧卧位和后入路进行。术后通过骨盆 X 线片和 CT 扫描确定髋臼杯位置。
导航组髋臼杯外展角平均为 39.2°±4.6°（范围 27°至 50°），前倾角平均为 14.6°±6.1°（范围 1°至 27.5°），常规组髋臼杯外展角平均为 42.9°±8.0°（范围 23°至 73°），前倾角平均为 11.6°±7.7°（范围-12.1°至 25°）。导航组髋臼杯外展角的变化较小（P=0.001）。导航组的杯置位偏差明显低于常规组（P=0.001，0.016）。常规组 55 个髋臼杯中有 37 个位于 Lewinnek 安全区，而导航组 55 个髋臼杯中有 51 个位于该安全区（P=0.006）。导航程序比传统技术平均多耗时 10 分钟。
使用便携式、基于加速度计的髋关节导航系统可改善 THA 中的髋臼杯置位。
