Center for Joint Surgery, Southwest Hospital, Third Military Medical University (Army Medical University), No. 30 Gaotanyan Street, Shapingba District, Chongqing, 400038, China.
Knee Surg Sports Traumatol Arthrosc. 2023 Apr;31(4):1524-1532. doi: 10.1007/s00167-021-06753-y. Epub 2021 Oct 5.
Femoral bowing influences the genesis and management of knee osteoarthritis (OA). The aim of this study was to investigate the relationship between the femoral torsion angle (FTA) and femoral bowing angle (FBA) in a southern Chinese population. It was hypothesized that a greater FTA would lead to a greater lateral FBA.
A total of 381 lower extremities from 381 osteoarthritic patients (298 women, 83 men; 201 left, 180 right; mean age 66.5 ± 8.9 years) were retrospectively reviewed. Age, sex, body mass index (BMI), side, height, femoral length (FL), hip-knee-ankle angle (HKA) and FTA were set as FBA-related factors. The three-dimensional (3D) FBA, the angle between the anatomical axis of the proximal femur and the anatomical axis of the distal femur in the plane they form, and its projection on the coronal (lateral FBA) and sagittal (anterior FBA) planes were measured on 3D computed tomography (CT) models. The correlation of the 3D, lateral and anterior FBAs with each of the FBA-related factors was explored using multiple linear regression analysis. The correlation between the FBA and FTA was explored and verified after using propensity score matching to control for the other FBA-related factors.
The mean lateral and anterior FBAs were 5.5°, with 53.5% greater than 5°, and 12.7°, with 70.3% greater than 11°, respectively. 3D FBA was positively correlated with age (Std.Co = 0.113, P < 0.05) and HKA (Std.Co = 0.129, P < 0.05). Lateral FBA was positively correlated with age (Std.Co = 0.118, P < 0.05), female sex (Std.Co = 0.206, P < 0.05), HKA (Std.Co = 0.184, P < 0.05) and FL (Std.Co = 0.220, P < 0.05). Anterior FBA was positively correlated with age (Std.Co = 0.108, P < 0.05) and male sex (Std.Co = 0.108, P < 0.05). When the related factors were balanced between the two groups (NS), FTA did not significantly affect 3D FBA or anterior FBA (NS), while FTA was positively correlated with lateral FBA (Std.Co = 0.165, P < 0.05).
External torsion of the proximal femur increases the lateral FBA by twisting a partial anterior FBA into a lateral FBA, especially in the female population. If a patient is found to have a large lateral FBA preoperatively, one should be alert to the possibility of a concomitant large FTA, as there are implications for femoral orthopedics, TKA and patellofemoral pressure distribution.
III.
股骨弯曲会影响膝关节骨关节炎（OA）的发生和治疗。本研究旨在调查中国南方人群中股骨扭转角（FTA）与股骨弯曲角（FBA）之间的关系。研究假设较大的 FTA 会导致更大的外侧 FBA。
回顾性分析了 381 例骨关节炎患者（298 名女性，83 名男性；201 例左侧，180 例右侧；平均年龄 66.5±8.9 岁）的 381 条下肢数据。年龄、性别、体重指数（BMI）、侧别、身高、股骨长度（FL）、髋膝踝角（HKA）和 FTA 被设定为 FBA 相关因素。在三维（3D）CT 模型上测量股骨近端解剖轴与股骨远端解剖轴在它们形成的平面上的 3D FBA 及其在冠状面（外侧 FBA）和矢状面（前侧 FBA）上的投影。使用多元线性回归分析探讨 3D、外侧和前侧 FBA 与各 FBA 相关因素之间的相关性。使用倾向评分匹配来控制其他 FBA 相关因素后，探讨并验证了 FBA 与 FTA 之间的相关性。
平均外侧和前侧 FBA 分别为 5.5°和 12.7°，其中 53.5%大于 5°，70.3%大于 11°。3D FBA 与年龄（Std.Co=0.113，P<0.05）和 HKA（Std.Co=0.129，P<0.05）呈正相关。外侧 FBA 与年龄（Std.Co=0.118，P<0.05）、女性（Std.Co=0.206，P<0.05）、HKA（Std.Co=0.184，P<0.05）和 FL（Std.Co=0.220，P<0.05）呈正相关。前侧 FBA 与年龄（Std.Co=0.108，P<0.05）和男性（Std.Co=0.108，P<0.05）呈正相关。当两组之间的相关因素达到平衡（NS）时，FTA 并不显著影响 3D FBA 或前侧 FBA（NS），而 FTA 与外侧 FBA 呈正相关（Std.Co=0.165，P<0.05）。
股骨近端的外旋增加了外侧 FBA，通过将部分前侧 FBA 扭曲成外侧 FBA 来实现，尤其是在女性人群中。如果术前发现患者存在较大的外侧 FBA，则应警惕可能同时存在较大的 FTA，因为这对股骨矫形、全膝关节置换术和髌股压力分布有影响。
III。
