Parratte S, Argenson J-N, Flecher X, Aubaniac J-M
Service de Chirurgie Orthopédique, Hôpital Sainte-Marguerite, 270, boulevard Sainte-Marguerite, BP 29, 13274 Marseille Cedex 09.
Rev Chir Orthop Reparatrice Appar Mot. 2007 May;93(3):238-46. doi: 10.1016/s0035-1040(07)90245-7.
Actetabular component malpositioning during total hip arthroplasty (THA) increases the risk of dislocation, reduces the range of motion, and can be the cause of early wear and loosening. There have been numerous reports on the optimal orientation of the acebaular component in THA. Lewinnek et al recommended an abduction angle of 40+/-10 degrees and an anteversion of 15+/-10 degrees for cup alignment in THA. In order to prevent malpostioned hip implants and improve the reproducibility of implant alignment in THA, numerous computer-assisted orthopedic systems have been described, using computed tomography (CT)-base or imageless navigation. Among the imageless systems available, one is based on Bone Morphing technology initially described by Stindel for computer-assisted knee arthroplasty and adapted for THA. The purpose of this study was to compare computer-assisted acetabular component insertion versus free hand placement.
A controlled randomized matched prospective study was performed in two groups of 30 patients. The study was approved by the French Ethics Committee. In the first group, cup positioning was assisted by an imageless computer-assisted orthopedics system based on Bone Morphing(R) (CAOS+ group). In the control group, cup placement was free hand (CAOS- group). The same cementless cup was used in both groups. The same surgeon performed all procedures using an anterolateral approach. Cup anteversion and abduction angles were measured on 3D CT scan reconstructions obtained postoperatively for each patient by an independent observer using a special cup evaluation software.
There were 16 males and 14 females in each group, mean age was 62 years (range 24-80) years, and mean body mass index was 25 in each group. Mean additional time of the CAOS procedure was 12 minutes (range 8-20). Intraoperative subjective agreement of the surgeon with the computer guidance system demonstrated a high correlation in 23 cases, a weak correlation in six cases and poor correlation in one case. There were no statistical differences between the CAOS+ and the CAOS- group regarding means of the abduction and anteversion angles, but a significant range of variance, the lowest variations being observed in the CAOS+ group.
This study has shown the accuracy of cup positioning using a CT-free navigation system in a prospective randomized controlled protocol.
全髋关节置换术（THA）期间髋臼组件位置不当会增加脱位风险，减少活动范围，并可能导致早期磨损和松动。关于THA中髋臼组件的最佳方向已有大量报道。Lewinnek等人建议THA中髋臼杯对齐的外展角度为40±10度，前倾角为15±10度。为了防止髋关节植入物位置不当并提高THA中植入物对齐的可重复性，已经描述了许多计算机辅助骨科系统，这些系统使用基于计算机断层扫描（CT）或无图像导航技术。在现有的无图像系统中，有一种基于最初由Stindel描述的用于计算机辅助膝关节置换术并适用于THA的骨变形技术。本研究的目的是比较计算机辅助髋臼组件插入与徒手放置。
对两组各30例患者进行了一项对照随机匹配前瞻性研究。该研究得到了法国伦理委员会的批准。在第一组中，髋臼杯定位由基于骨变形（R）的无图像计算机辅助骨科系统辅助（CAOS +组）。在对照组中，髋臼杯放置是徒手操作（CAOS -组）。两组均使用相同的非骨水泥髋臼杯。同一位外科医生采用前外侧入路进行所有手术。术后由一名独立观察者使用特殊的髋臼杯评估软件在每位患者的3D CT扫描重建上测量髋臼杯的前倾角和外展角度。
每组有16名男性和14名女性，平均年龄为62岁（范围24 - 80岁），每组的平均体重指数为25。CAOS手术的平均额外时间为12分钟（范围8 - 20分钟）。术中外科医生与计算机引导系统的主观一致性在23例中显示出高度相关性，6例中显示出弱相关性，1例中显示出差相关性。CAOS +组和CAOS -组在外展角度和前倾角的平均值方面没有统计学差异，但存在显著的方差范围，在CAOS +组中观察到的变化最小。
本研究在一项前瞻性随机对照方案中显示了使用无CT导航系统进行髋臼杯定位的准确性。
