Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong, China.
Gait Posture. 2011 Apr;33(4):721-3. doi: 10.1016/j.gaitpost.2011.02.005. Epub 2011 Mar 4.
Ankle-foot orthoses (AFOs) are commonly prescribed to improve gait. The stiffness of an AFO is central for successful prescription; however, the recommended level of stiffness is currently based on the experience of clinicians. Therefore, the aim of this study was to design an experimental AFO (EAFO) whose stiffness was adjustable using commercially available oil-damper joints, and to demonstrate its potential capability in investigating the effects of altering AFO stiffness on gait. The influence of the EAFO stiffness on ankle joint kinematics in sagittal plane was evaluated in 10 patients with stroke by altering the stiffness of its oil-damper- type orthotic ankle joints using the four levels pre-set and defined by the manufacturer in dorsi- and plantarflexion directions independently. The mean peak plantarflexion angle was reduced by 105%, showing a change from 8.18 (3.14) degrees of plantarflexion to 0.38 (4.17) degrees of dorsiflexion, whilst the mean peak dorsiflexion angle was reduced by 44%, showing a change from 11.46 (5.57) degrees of dorsiflexion to 6.47 (5.23) degrees of dorsiflexion by altering the EAFO stiffness. The EAFO would therefore serve as a convenient tool when investigating the influence of AFO stiffness on gait in both clinical and research settings.
踝足矫形器（AFO）常用于改善步态。AFO 的刚度对于成功处方至关重要；然而，目前推荐的刚度水平是基于临床医生的经验。因此，本研究旨在设计一种实验性的 AFO（EAFO），其刚度可以使用市售的油阻尼关节进行调节，并展示其在研究改变 AFO 刚度对步态的影响方面的潜在能力。通过在背屈和跖屈方向上分别使用制造商预设和定义的四个级别来改变其油阻尼型矫形踝关节的刚度，评估了 EAFO 刚度对 10 名脑卒中患者矢状面踝关节运动学的影响。平均峰值跖屈角度减小了 105%，从跖屈 8.18（3.14）度变为背屈 0.38（4.17）度，而平均峰值背屈角度减小了 44%，从背屈 11.46（5.57）度变为背屈 6.47（5.23）度。因此，当在临床和研究环境中研究 AFO 刚度对步态的影响时，EAFO 将成为一种方便的工具。
