Objective: To analyze the distribution characteristics of foot deformities and the biomechanical features of the feet among elderly diabetic patients in the community. Methods: A total of 3 148 elderly diabetic patients (6 296 feet) who participated in the diabetic foot screening program in Jinshan District, Shanghai, from March to May 2023 were included, with 1 357 males and 1 791 females, aged (70.7±6.0) years. According to arch deformities, the severity of hallux valgus, and the presence or absence of other toe deformities (hammer foot, mallet foot, and claw foot), the patients were grouped and compared in terms of biomechanical parameters such as plantar pressure, force-bearing area, foot axis angle, footprint length, and load ratio. Results: The the most common foot deformity was the combination of arch deformities, accounting for up to 41.0% (2 581/6 296), it was followed by hallux valgus at 21.8% (1 371/6 296) and other toe deformities at 13.4% (846/6 296). A total of 56.5% (3, 557/6 296) of the patients had at least one type of foot deformity, and 29.0% (1 032/3 557) presented with tow or more types of foot deformities. When grouped according to arch deformities, the patients in the low arch group, mild low arch group, normal arch group, mild high arch group, and high arch group was 343, 1 282, 3 715, 595, and 361 cases, respectively; and there were statistically significant differences in maximum pressure, mean pressure, force-bearing area, foot axis angle, anterior-posterior and lateral offsets of the center of plantar pressure, anterior-posterior foot load ratio, and medial-lateral load ratio among all the groups (all P<0.001). The high arch group exhibited the highest maximum and mean pressures on the plantar surface, with the smallest force-bearing area, while the opposite was true for the low arch group (all P<0.001). There were 4 925, 731, 640 cases in the no hallux valgus group, mild hallux valgus group, and moderate-to-severe hallux valgus group respectively when grouped according to the severity of hallux valgus. The moderate-to-severe hallux valgus group had the lowest medial load (P=0.002) and the highest lateral load ratio (P=0.001). Compared to the group without other toe deformities (n=5 450), the group with other toe deformities (n=846) exhibited higher maximum plantar pressure [(214.43±112.85) vs (202.88±113.63) kPa, P<0.001], a lower forefoot load ratio (54.35%±13.31% vs 55.94%±12.58%, P=0.001), and a higher hindfoot load ratio (45.65%±13.31% vs 44.06%±12.58%, P=0.001). Conclusions: Among elderly diabetic patients, the incidence rate of foot deformities is as high as 56.5%, with arch deformities being the most common. Foot mechanics analysis indicates that the high arch group has the highest maximum and average plantar pressures, but the smallest force-bearing area, while the opposite is true for the low arch group. Toe deformities can affect the patient's plantar load ratio.
目的： 分析社区老年糖尿病人群足部畸形分布及生物力学特征。 方法： 纳入2023年3至5月参加上海市金山区糖尿病足筛查项目的3 148例老年糖尿病患者（6 296只足），男1 357例，女1 791例，年龄（70.7±6.0）岁。依据足弓畸形、拇外翻严重程度及是否存在其他足趾畸形（锤状足、槌状足和爪状足）分组，比较不同分组情况各组足底压强、受力面积、足轴角、足印长度及负荷比等生物力学参数的差异。 结果： 足畸形分布情况可见，合并足弓畸形最多，高达41.0%（2 581/6 296），其次为拇外翻21.8%（1 371/6 296）和其他足趾畸形13.4%（846/6 296）。56.5%（3 557/6 296）合并一种足畸形，29.0%（1 032/3 557）合并两种及以上的足畸形。依据足弓畸形分组（低足弓组、轻微低足弓组、正常足弓组、轻微高足弓组及高足弓组分别为343、1 282、3 715、595、361例），各组最大压强、平均压强、受力面积、足轴角、足底压力中心前后及侧向偏移量、前后足负荷比和内外侧负荷比差异均有统计学意义（均P<0.001），高足弓组足底最大压强及平均压强最高，而受力面积最小，低足弓组反之（均P<0.001）。依据拇外翻严重程度分组（无拇外翻组、轻度拇外翻组、中-重度拇外翻组分别为4 925、731、640例），中-重度拇外翻组内侧负荷最低（P=0.002），而外侧负荷比最高（P=0.001）。有其他足趾畸形组（n=846）较无其他足趾畸形组（n=5 450）足底最大压强高［（214.43±112.85）比（202.88±113.63）kPa， P<0.001］、前足负荷比低（54.35%±13.31%比55.94%±12.58%， P=0.001）、后足负荷比高（45.65%±13.31%比44.06%±12.58%，P=0.001）。 结论： 老年糖尿病人群中合并足畸形比例高达56.5%，合并足弓畸形的最高。足部力学分析提示，高足弓组足底最大压强及平均压强最高，而受力面积最小，低足弓组反之。足趾畸形会影响患者足底的负荷比。.