A pilot study investigating the effect of ankle-foot orthosis (AFO) stiffness on walking patterns of patients with ankle impairment

Rights statement
Awarding institution
  • University of Strathclyde
Date of award
  • 2017
Thesis identifier
  • T15059
Person Identifier (Local)
  • 201670522
Qualification Level
Qualification Name
Department, School or Faculty
  • Ankle- foot orthoses (AFO) are commonly utilized as one of the standard treatments to improve ambulation in stroke patients. However, AFOs are prescribed and customized to individual patient in a variety of designs by healthcare professionals because there is a lack of strong level of evidence-based studies. In addition, the influence of AFOs’ mechanical properties on functional deficit or clinical impairment is still not well understood. Therefore, this study aims to evaluate the biomechanical effects of commonly used AFOs on the lower extremities during the gait cycle. A healthy subject volunteered to be tested walking firstly without an AFO as a control and then wearing a solid carbon fibre reinforced, a solid and two posterior leaf spring AFOs. Strain gauges were attached to each AFO at ankle level to allow the measurement of the moment generated by the orthosis in the sagittal plane. The subject, wearing each instrumented AFO walked in the gait analysis laboratory where kinematic and kinetic data were acquired. This method allows the contribution of the AFOs during walking to be determined, and this information in conjunction with the kinematic and kinetic data, the anatomical moments, which are the moments generated by the muscles and ligaments can be calculated. The results imply that an AFO that is stiffer than the optimal requirement could lead to restriction of ankle motion during the stance phase and have an indirect effect on the knee and hip joints. The findings suggest that the stiffness of AFO, applied in stroke patients should be tailored base on the clinical impairment to get the optimum benefit. It is planned to continue this investigation on stroke patients.
Advisor / supervisor
  • Solomonidis, Stephanos
Resource Type
Embargo Note
  • The digital version of this thesis is restricted to Strathclyde users only