Background

The risk of falls during locomotion increases with age, and step negotiation is one of the most hazardous types of gait for older adults. Further, a history of a fall is one of the strongest predictors of a future fall; and women fall more frequently, and incur greater medical costs, compared to men. The purpose of the study was to identify lower extremity kinematic factors associated with transition step clearance and foot placement in young women and older women with and without a fall history.

Methods

Forty-five female participants (15 per group) completed trials that consisted of walking barefoot along a raised walkway at a self-selected speed, descending a 17 cm step, and continued level ground walking. Variables of interest included lead and trail limb minimum step clearance and foot placement, and bilateral lower extremity joint positions at step clearance and at lead foot initial contact.

Findings

Significant group differences, with large effect sizes, were found in lead foot placement and knee flexion position at initial contact. Both older groups landed more closely to the step and made initial contact with the lead knee in a more flexed position compared to the young group.

Interpretation

The kinematic differences may be a strategy utilized by older adults to create an early landing to minimize time in single limb stance and compensate for age-related loss of lower extremity strength, range of motion, and/or balance. However, the greater knee flexion may also increase the risk a fall due to lead limb collapse.

背景

运动过程中跌倒的风险随着年龄的增长而增加，步态谈判是老年人最危险的步态之一。此外，跌倒的历史是未来跌倒的最强预测因素之一。与男性相比，女性跌倒更频繁，医疗费用也更高。该研究的目的是确定与有或没有跌倒史的年轻女性和老年女性的过渡步间隙和足部放置相关的下肢运动学因素。

方法

45 名女性参与者（每组 15 名）完成了包括以自选速度赤脚沿着升高的人行道行走、下降 17 厘米的台阶和继续平地行走的试验。感兴趣的变量包括前肢和后肢最小步距和足部位置，以及步距和前脚初始接触时的双下肢关节位置。

发现

在初始接触时的铅脚放置和膝关节屈曲位置方面发现了显着的组间差异，具有较大的效应量。与年轻组相比，两个年龄较大的组都更靠近台阶并以更弯曲的位置与前膝进行初始接触。

解释

运动学差异可能是老年人使用的一种策略，用于创建早期着陆以最大限度地减少单肢站立时间并补偿与年龄相关的下肢力量、运动范围和/或平衡损失。然而，更大的膝关节屈曲也可能增加因肢体塌陷而跌倒的风险。