Brunner Alexander, Horisberger Monika, Herzog Richard F
Department of Orthopedic Surgery, Cantonal Hospitals Lucerne, Wolhusen, Switzerland.
Arthroscopy. 2009 Apr;25(4):382-91. doi: 10.1016/j.arthro.2008.11.012. Epub 2009 Feb 11.
The purpose of this study was to investigate the impact of a new computed tomography-based computer navigation system on the accuracy of arthroscopic offset correction in patients with cam type femoroacetabular impingement (FAI), and to evaluate if the accuracy of offset restoration compromises the early clinical outcome.
We prospectively treated 50 patients (25 navigated and 25 non-navigated) by hip arthroscopy and arthroscopic offset restoration for cam FAI. The patients were a mean age 42.9 years, and the average follow-up was 26.7 months, with no patients lost to follow-up. Magnetic resonance imaging scans were performed preoperatively and 6 weeks postoperatively. A postoperative alpha angle of less than 50 degrees or a reduction of the alpha angle of more than 20 degrees was considered to be successful offset restoration. Outcomes were measured with a visual analogue scale for pain, range of motion, and the nonarthritic hip score.
The mean alpha angle improved from 76.5 degrees (range, 57 degrees to 110 degrees) to 54.2 degrees (range, 40 degrees to 84 degrees). In both the navigated and the non-navigated groups, 6 patients (24%) showed insufficient offset correction. Range of motion, visual analogue scale for pain scores, and nonarthritic hip scores significantly improved in all subgroups. Statistical analysis showed no significant difference regarding the clinical outcome between patients with sufficient and insufficient correction of the alpha angle.
In this series, a significant percentage of patients (24%) showed an insufficient correction of the alpha angle after hip arthroscopy for cam FAI. This study shows that the presented navigation system could not improve this rate and that the insufficient accuracy of reduction of the alpha angle does not appear to compromise the early clinical outcome.
Level II, prospective comparative study.
本研究旨在探讨一种基于计算机断层扫描的新型计算机导航系统对凸轮型股骨髋臼撞击症（FAI）患者关节镜下偏心距矫正准确性的影响，并评估偏心距恢复的准确性是否会影响早期临床疗效。
我们对50例凸轮型FAI患者进行了前瞻性髋关节镜检查及关节镜下偏心距恢复治疗（25例使用导航，25例未使用导航）。患者平均年龄42.9岁，平均随访26.7个月，无失访患者。术前及术后6周进行磁共振成像扫描。术后α角小于50度或α角减小超过20度被认为是成功的偏心距恢复。采用视觉模拟评分法评估疼痛、活动范围和非关节炎髋关节评分。
平均α角从76.5度（范围57度至110度）改善至54.2度（范围40度至84度）。在导航组和非导航组中，均有6例患者（24%）偏心距矫正不足。所有亚组的活动范围、疼痛视觉模拟评分和非关节炎髋关节评分均显著改善。统计分析显示，α角矫正充分与不充分的患者之间临床疗效无显著差异。
在本系列研究中，相当比例（24%）的凸轮型FAI患者髋关节镜检查后α角矫正不足。本研究表明，所介绍的导航系统未能提高这一比例，且α角复位准确性不足似乎并未影响早期临床疗效。
II级，前瞻性比较研究。
