研究膝关节形态差异性，分析两款膝关节假体系统的使用情况，并确定哪种因素与使用假体宽窄有关。

回顾性收集2019年1月至2021年1月解放军总医院接受初次人工全膝关节置换术的616例患者，其中348例使用Legion膝关节假体系统(Smith&Nephew公司，美国)，268例使用Unique膝关节假体系统(正天公司，天津)。仅纳入原发性膝骨关节炎的患者，排除有任何手术史或膝关节创伤病史、大量骨缺损需植骨、内/外翻畸形大于15°的患者。统计患者的性别、身高、使用假体型号等信息。用pearson相关分析、二分类logistic回归分析等方法分析性别、身高、股骨尺寸与假体宽窄选择的关系。

Unique组使用最多的两个股骨假体尺寸均比Legion组更窄(58/60 vs 58/62；61/63 vs 61/66)。两组女性拥有更小更窄的股骨，汇总两组所有患者，男性左右径/前后径(ML/AP)比值为(1.08±0.03)，女性约ML/AP比值为(1.07±0.03)；男女之间差异有统计学意义(t＝－4.75，P<0.05)。采用二分类logistic回归分析评估性别、身高、股骨尺寸对使用窄版假体的影响发现，发现性别是相关性最大的因素。在Legion组中女性使用窄版假体的概率是男性的4.41倍[OR＝4.41, 95%CI(1.97，9.85)，P<0.01]；在Unique假体中女性是男性的7.11倍[OR＝7.11，95%CI(2.71，18.61)，P<0.01]。其次是股骨的尺寸，股骨尺寸越大窄版假体的使用率越大。

性别之间膝关节形态存在差异，但是不管是女性还是男性都有相当多的人使用窄版的假体。应考虑种族差异，针对亚洲人群设计假体，并增加假体型号，减少型号间的差值。

To study the morphological differences of knee joints by analyzing the use of two knee prosthesis systems and determine which factors are related to the use of prosthesis width.

From January 2019 to January 2021, 616 patients who underwent primary total knee arthroplasty in PLA General Hospital were retrospectively collected. Among them, 348 patients used Legion knee prosthesis system (Smith&Nephew Company, USA) and 268 patients used Unique knee prosthesis system (Zhengtian Company, Tianjin). Only patients with primary knee osteoarthritis were included, and patients with any history of surgery or knee joint trauma, a large number of bone defects requiring bone grafting and varus/valgus deformity greater than 15° were excluded. Statistics of gender, height, prosthesis type and other information were made. Pearson correlation analysis and binary logistic regression analysis were used to analyze the relationship between sex, height, femur size and prosthesis width selection.

The two most frequently used femoral prostheses in the Unique group were both narrower in size than those in the Legion group (58/60 vs 58/62; 61/63 vs 61/66). Women in both groups had smaller and narrower femurs. The medial-lateral/anterior-posterior(ML/AP) ratio was (1.08±0.03) in men and (1.07±0.03) in women. There was statistically significant difference between male and female (t=-4.75, P<0.05). Binary logistic regression analysis was used to evaluate the influence of gender, height, and femur size on the use of narrow prosthesis, and it was found that gender was the most relevant factor. In Legion group, women were 4.41 times more likely to use narrow prosthesis than men [OR=4.41, 95%CI (1.97, 9.85), P<0.01]. In the Unique prosthesis, women were 7.11 times more than men [OR=7.11, 95%CI (2.71, 18.61), P<0.01]. The second is the size of the femur. The larger the size of the femur, the higher the utilization rate of narrow prosthesis.

There are differences in knee joint morphology between males and females, but there are quite a number of women and men who use narrow prosthesis. Ethnic differences should be taken into account to design components for Asian populations and the femoral component size options should be increased with lesser increments in between sizes.