Manuscript title: The effect of three dimensional printing hinged ankle foot orthosis in chronic stroke patients

Abstract BackgroundThree-dimensional printing (3DP) is a promising technique utilized in orthosis fabrication, including ankle foot orthosis for stroke patients. However, the effects on ankle biomechanics remains unclear. ObjectivesTo compare the plantar pressure distribution and patient’s subjective experience in chronic stroke patients during 3DP hinged ankle foot orthosis (3DP-HAFO) and anterior ankle foot orthosis (A-AFO) walking MethodsTen patients with first-ever unilateral stroke were enrolled in this study. All patients performed 10-meter walk test in 3 different conditions, including 3DP-HAFO walking, A-AFO walking, and bare foot walking. The plantar pressure parameters including contact area, maximum force, and peak pressure were collected using Pedar X insole system. Gait asymmetry analysis of the plantar pressure parameters was conducted. Quebec User Evaluation of Satisfaction with Assistive Technology (QUEST) was used for patient’s satisfaction.Results3DP-HAFO walking revealed significant increase in medial midfoot peak pressure compared to bare foot walking. Gait asymmetry analysis illustrated more even medial midfoot contact area during 3DP-HAFO walking compared to bare foot walking while A-AFO walking did not. In QUEST survey, 3DP-HAFO outweighs A-AFO in fitting and durableness. Conclusions3DP-HAFO may improve ankle instability and gait asymmetry in chronic stroke patients.