The number of patients with unilateral above-knee amputation (AKA) due to non-vascular causes has remained stable over the years, at 0.92 per 1000 people per year. Post-AKA individuals are at risk of experiencing a higher incidence of chronic pain. Post rehabilitation, it is estimated that between 16–62% of patients with musculoskeletal disabilities fail to meet the minimum criteria for physical activity in comparison to a healthy population. The current study included 14 participants (11 men and 3 women) with a mean age of 46.1 ± 14.2 years, body height of 1.76 ± 0.09 m, and weight of 79.6 ± 18.3 kg, who were all post-unilateral above-the-knee amputees. Patients in the study were divided into two groups: active (AC) and non-active (NAC). This study was conducted in a certified Laboratory of Biomechanical Analysis using the BTS Smart-E system (BTS Bioengineering). In order to investigate the symmetry function (SF) of gait, the only measurements included were the time series assessment of gait variables defining pelvic and lower limb joint motion and ground reaction forces (GRF). Both groups had an asymmetrical gait pattern with a different magnitude and relative position in the gait cycle, which was revealed by SF. The differences in terms of median, minimum, and maximum were statistically significant (p < 0.05), with SF ranging from –25 to 24% for the AC group and from 43 to 77% (59% on average) for the NAC group. The AC’s pattern was more symmetrical compared to the NAC’s pattern, especially in the case of pelvic and hip joint motion.

中文翻译：

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对称函数：主动和非主动膝上截肢者的区别

由于非血管原因导致单侧膝上截肢 (AKA) 的患者人数多年来一直保持稳定，每年每 1000 人中有 0.92 人。AKA 后个体有更高的慢性疼痛发生率。康复后，据估计，与健康人群相比，有 16-62% 的肌肉骨骼残疾患者未能达到身体活动的最低标准。目前的研究包括 14 名参与者（11 名男性和 3 名女性），平均年龄 46.1 ± 14.2 岁，身高 1.76 ± 0.09 m，体重 79.6 ± 18.3 kg，他们都是单侧膝盖以上术后截肢者。研究中的患者分为两组：活动组 (AC) 和非活动组 (NAC)。这项研究是在经过认证的生物力学分析实验室中使用 BTS Smart-E 系统（BTS 生物工程）进行的。为了研究步态的对称函数 (SF)，唯一包括的测量是定义骨盆和下肢关节运动和地面反作用力 (GRF) 的步态变量的时间序列评估。SF 揭示了两组在步态周期中具有不同幅度和相对位置的不对称步态模式。中位数、最小值和最大值的差异具有统计学意义（SF 揭示了两组在步态周期中具有不同幅度和相对位置的不对称步态模式。中位数、最小值和最大值的差异具有统计学意义（SF 揭示了两组在步态周期中具有不同幅度和相对位置的不对称步态模式。中位数、最小值和最大值的差异具有统计学意义（p < 0.05)，AC 组的 SF 范围为 –25% 至 24%，NAC 组的 SF 范围为 43% 至 77%（平均 59%）。与 NAC 的模式相比，AC 的模式更加对称，尤其是在骨盆和髋关节运动的情况下。