Department of Knee Surgery, Luoyang Orthopedic-Traumatological Hospital (Henan Orthopedic Hospital), Qiming Southern Road, Luoyang, Henan 471002, China.
Biomed Res Int. 2021 Feb 18;2021:8813300. doi: 10.1155/2021/8813300. eCollection 2021.
The purpose of this study was to evaluate the usefulness of preoperative planning of the femurofibular angle (FFA) in medial open-wedge high tibial osteotomy (OWHTO) for mild medial knee osteoarthritis.
Thirty-two patients (32 knees) with mild medial knee OA were retrospectively reviewed. The patients underwent preoperative planning of the FFA for OWHTO. For preoperative planning, a full-length weight-bearing X-ray photograph of the lower limb was opened within Adobe Photoshop Software, and a targeted corrective mechanical axis line of the lower limb and its intersecting point at the lateral tibial plateau surface was drawn using rectangle selection and filling tools. A frame, which encircled the tibia and fibula, was created around the predicted osteotomy plane and then rotated until the ankle center was on the targeted mechanical axis line. Subsequently, a distal femoral condyle line and a proximal fibula axis line were drawn, and the angle between the two lines was measured and defined as the femurofibular angle (FFA). During biplane OWHTO, the preoperatively determined FFA was used to complete the correction of the mechanical axis. During follow-up, the postoperative mechanical weight-bearing line (WBL) of the lower limb, the mechanical femorotibial angle (mFTA), and the FFA were measured and compared with the preoperatively determined values.
The mechanical WBL shifted from a preoperative value of 25.36 ± 5.02% to a postoperative value of 56.19 ± 0.10% from the medial border along the mediolateral width of the tibial plateau, and it was 56.57 ± 0.08% at the final follow-up ( < 0.01). The preoperatively determined value was 56.25%, and no significant difference was found compared with postoperative week-one and final follow-up values ( > 0.05). The mFTA was corrected from a preoperative varus of 4.02 ± 0.63° to a postoperative week-one valgus of 2.37 ± 0.28°, and it had a valgus of 2.48 ± 0.39° at the final follow-up ( < 0.01). No significant difference in the valgus was found compared with the postoperative week-one, final follow-up and preoperatively determined valgus of 2.34 ± 0.26° ( > 0.05). The postoperative week-one and final follow-up FFAs were 90.34 ± 1.53° and 90.33 ± 1.52°, respectively, and no significant difference was found compared with the preoperatively determined value of 90.12 ± 1.72° and the intraoperative setting value of 90.25 ± 1.67° ( > 0.05). All corrected values were within the acceptable range of preoperative planning.
Preoperative planning of the FFA may be useful in OWHTO for patients with mild medial knee OA. Satisfactory correction of the postoperative targeted mechanical axis line of the lower limb can be obtained.
本研究旨在评估术前规划股腓角（FFA）在轻度内侧膝关节骨关节炎内侧开放楔形胫骨高位截骨术（OWHTO）中的作用。
回顾性分析 32 例（32 膝）轻度内侧膝关节骨关节炎患者。患者接受了 OWHTO 的 FFA 术前规划。术前规划时，在 Adobe Photoshop 软件中打开下肢全长负重 X 线片，使用矩形选择和填充工具绘制下肢靶向矫正机械轴线及其在外侧胫骨平台表面的交点。在预测截骨平面周围创建一个环绕胫骨和腓骨的框架，然后旋转框架，直到踝关节中心位于靶向机械轴线上。随后，绘制股骨远端髁线和腓骨近端轴线，测量并定义两条线之间的角度为股腓角（FFA）。在双平面 OWHTO 中，使用术前确定的 FFA 完成机械轴的矫正。随访时，测量并比较下肢术后机械负重线（WBL）、机械股骨胫骨角（mFTA）和 FFA 与术前确定的值。
下肢机械 WBL 从内侧胫骨平台的内外宽度沿内侧边界从术前的 25.36±5.02%转移到术后的 56.19±0.10%，最终随访时为 56.57±0.08%（<0.01）。术前确定的值为 56.25%，与术后 1 周和最终随访时的值相比，无显著差异（>0.05）。mFTA 从术前的内翻 4.02±0.63°矫正至术后 1 周的外翻 2.37±0.28°，最终随访时外翻 2.48±0.39°（<0.01）。与术后 1 周、最终随访和术前确定的外翻 2.34±0.26°（>0.05）相比，外翻无显著差异。术后 1 周和最终随访时的 FFA 分别为 90.34±1.53°和 90.33±1.52°，与术前确定的 90.12±1.72°和术中设定的 90.25±1.67°无显著差异（>0.05）。所有矫正值均在术前规划的可接受范围内。
术前规划 FFA 可能对轻度内侧膝关节骨关节炎患者的 OWHTO 有用。可以获得下肢术后靶向机械轴的满意矫正。
