Steadman Philippon Research Institute, 181 W. Meadow Dr. Ste 1000, Vail, CO, 81637, USA.
Cincinnati Sports Medicine Center, Cincinnati, OH, USA.
Knee Surg Sports Traumatol Arthrosc. 2019 Oct;27(10):3105-3109. doi: 10.1007/s00167-018-4933-3. Epub 2018 Apr 11.
The most commonly used parameter for defining cam-type femoroacetabular impingement(FAI) has been the alpha angle. The purpose of this study was to determine if patient-reported outcomes 5 years following hip arthroscopy for FAI were associated with postoperative alpha angle. We hypothesized that patient-reported outcomes would not be influenced by postoperative alpha angle in patients with FAI.
230 patients had primary hip arthroscopy for FAI and chondrolabral dysfunction. The median age was 40 years (range 18-69). All patients had preoperative and 1 day postoperative alpha angles recorded. At minimum 5 years following arthroscopy, all patients completed an online questionnaire that included the modified Harris Hip score(MHHS), WOMAC, HOS ADL, HOS Sport, SF12 and patient satisfaction. This study was IRB approved. Patients were grouped into two, based on their postoperative alpha angle: <55° (n = 158) and ≥ 55° (n = 56).
The median preoperative alpha angle was 72° (range 50°-105°) and the median postoperative alpha angle was 45° (range 30°-100°). The postoperative alpha angle did not correlate with any outcome measure. The median preoperative alpha angle in the < 55° group was 71° and in ≥ 55° group the median was 74° (p = 0.044). The median follow-up was 5.1 years (range 5-7). The median mHHS was 85 (range 47-100) in the < 55° and 85 (range 54-100) in the ≥ 55° group (n.s); WOMAC was 5 (range 0-73) in the < 55° and 4.5 (range 1-57) in the ≥ 55° group(n.s); HOS ADL was 95 (range 31-100) in the < 55° and 96 (range 50-100) in the ≥ 55° group (n.s); HOS Sport was 88 (range 0-100) in the < 55° and 88 (range 13-100) in the ≥ 55° group (n.s) Median patient satisfaction was 9 (range 1-10) in both groups.
This study shows no statistically significant differences between the investigated patient-reported outcome scores at a 5 years postoperatively in relation to a correction of the alpha angle to 55°. While alpha angle has been shown to be an excellent preoperative diagnostic tool, the postoperative angle does not correlate with midterm outcomes or the development of osteoarthritis based on patient symptoms. The amount of osteoplasty should be based on dynamic examination at arthroscopy, and not by alpha angle.
III Case-control, retrospective comparative study.
用于定义凸轮型股骨髋臼撞击症（FAI）的最常用参数一直是 alpha 角。本研究的目的是确定髋关节镜检查治疗 FAI 5 年后患者报告的结果是否与术后 alpha 角相关。我们假设在 FAI 患者中，患者报告的结果不会受到术后 alpha 角的影响。
230 例 FAI 和软骨盂唇功能障碍的患者接受了初次髋关节镜检查。中位年龄为 40 岁（18-69 岁）。所有患者均记录术前和术后 1 天的 alpha 角。在髋关节镜检查后至少 5 年，所有患者均完成了在线问卷调查，包括改良 Harris 髋关节评分（MHHS）、WOMAC、HOS ADL、HOS 运动、SF12 和患者满意度。本研究经 IRB 批准。根据术后 alpha 角将患者分为两组：<55°（n = 158）和≥ 55°（n = 56）。
术前 alpha 角的中位数为 72°（范围 50°-105°），术后 alpha 角的中位数为 45°（范围 30°-100°）。术后 alpha 角与任何结果测量值均无相关性。<55°组的术前 alpha 角中位数为 71°，≥ 55°组的中位数为 74°（p = 0.044）。中位随访时间为 5.1 年（范围 5-7 年）。<55°组的中位数 mHHS 为 85（范围 47-100），≥ 55°组为 85（范围 54-100）（无统计学差异）；WOMAC 在<55°组中为 5（范围 0-73），在≥ 55°组中为 4.5（范围 1-57）（无统计学差异）；HOS ADL 在<55°组中为 95（范围 31-100），在≥ 55°组中为 96（范围 50-100）（无统计学差异）；HOS 运动在<55°组中为 88（范围 0-100），在≥ 55°组中为 88（范围 13-100）（无统计学差异）。两组患者的满意度中位数均为 9（范围 1-10）。
本研究表明，在髋关节镜检查治疗 FAI 5 年后，与将 alpha 角校正至 55°相比，调查的患者报告的结果评分之间没有统计学上的显著差异。虽然 alpha 角已被证明是一种出色的术前诊断工具，但术后角度与中期结果或基于患者症状的骨关节炎发展无关。骨切除术的数量应基于关节镜下的动态检查，而不是 alpha 角。
III 级病例对照，回顾性比较研究。
