Design and Analysis of Knee Ankle Foot Orthosis (KAFO) for Paraplegia Person

Abstract

Knee ankle foot orthoses (KAFOs) are prescribed to paraplegic patients with low level spinal cord injury and with good control of the trunk muscles. Three types of KAFOs were used in this work (plastic-metal, metal-metal and composite materials), the composite materials were depended on the number of perlon layers (13 layers & 9 layers) with one layer of carbon-fiber and (6 layers) without carbon-fiber. The mechanical properties of most of the KAFOs' materials were tested by tensile test and fatigue machines. The data of gait cycle (Ground Reaction Force (GRF), and pressure distribution) were collected from one patient with poliomyelitis (wearing brace type KAFO) and one normal subject. In this paper, the FEM (ANSYS) was used to compute the safety factor of fatigue for all types of KAFOs' models and the equivalent stress (Von-Mises). The interface pressure between the patient's leg and the brace was tested by using a piezoelectric sensor. The results obtained from ANSYS gave the profile of safety factor of fatigue, for metal-metal KAFO (3.69), plastic-metal model (0.88). While, the (13) layers for composite material was about (1.4), but (1.07) & (0.41) for (9) layers and (6) layers, respectively. The value of safety factor increased with the composite material for the suggested design. ‫ﻧﻮع‬ ‫ﺻﻨﺎﻋﻲ‬ ‫ﻟﻤﺴﻨﺪ‬ ‫رﯾﺎﺿﻲ‬ ‫ﺗﺤﻠﯿﻞ‬ ‫و‬ ‫ﺗﺼﻤﯿﻢ‬) ‫ﻗﺪم‬-‫ﻛﺎﺣﻞ‬-‫رﻛﺒﺔ‬ (‫اﻟﺴﻔﻠﻰ‬ ‫اﻻطﺮاف‬ ‫ﻟﻤﻌﻮﻗﻲ‬ ‫اﻟﺧﻼﺻﺔ‬ ‫ف‬ ‫ﺗوﺻ‬ ‫اﻟ‬ ‫ﺎﻧد‬ ‫ﻣﺳ‬ ‫وع‬ ‫ﻧ‬) ‫ﺔ‬ ‫رﻛﺑ‬ ‫ل‬ ‫ﻛﺎﺣ‬ ‫دم‬ ‫ﻗ‬ (KAFO ‫ﻠل‬ ‫ﺷ‬ ‫ﻰ‬ ‫ﻟﻣرﺿ‬ ‫راف‬ ‫اﻻط‬ ‫ذوي‬ ‫ﻟ‬ ‫ﻔﻠﻰ‬ ‫اﻟﺳ‬ ‫اﻟﺷوﻛﻲ‬ ‫اﻟﺣﺑل‬ ‫ﻓﻲ‬ ‫اﻟطﻔﯾﻔﺔ‬ ‫اﻻﺻﺎﺑﺎت‬ ‫ذع‬ ‫اﻟﺟ‬ ‫ﻼت‬ ‫ﻋﺿ‬ ‫ﻲ‬ ‫ﻓ‬ ‫د‬ ‫ﺟﯾ‬ ‫م‬ ‫وﺗﺣﻛ‬. ‫ﺗ‬ ‫ن‬ ‫ﻣ‬ ‫واع‬ ‫اﻧ‬ ‫ﺔ‬ ‫ﺛﻼﺛ‬ ‫ﺗﺧدام‬ ‫اﺳ‬ ‫م‬ ‫اﻟﻣﺳﺎﻧد‬) ‫ﺑﻼﺳﺗﯾﻛﻲ‬-‫ﻣﻌدن‬ , ‫دن‬ ‫ﻣﻌ‬-‫دن‬ ‫ﻣﻌ‬ , ‫ﺔ‬ ‫ﻣرﻛﺑ‬ ‫واد‬ ‫ﻣ‬ (‫و‬ ‫أ‬ ‫م‬ ‫ﺗ‬ ‫ﻰ‬ ‫ﻋﻠ‬ ‫ﻼل‬ ‫واﻟﻛ‬ ‫د‬ ‫اﻟﺷ‬ ‫ص‬ ‫ﻓﺣ‬ ‫راء‬ ‫ﺟ‬ ‫واد‬ ‫ﻣ‬ KAFO ‫ﺔ‬ ‫اﻟﻣﯾﻛﺎﻧﯾﻛﯾ‬ ‫واص‬ ‫اﻟﺧ‬ ‫ﺔ‬ ‫ﻟدراﺳ‬. ‫ﺎس‬ ‫ﻗﯾ‬ ‫راء‬ ‫اﺟ‬ ‫م‬ ‫ﺗ‬ ‫ل‬ ‫اﻟﻔﻌ‬ ‫رد‬ ‫وة‬ ‫ﻗ‬) GRF (‫ﺎﻋدة‬ ‫ﺑﻣﺳ‬ ‫ﺎل‬ ‫اﻻطﻔ‬ ‫ﻠل‬ ‫ﺑﺷ‬ ‫ﺎب‬ ‫ﻣﺻ‬ ‫رﯾض‬ ‫ﻣ‬) ‫دي‬ ‫ﯾرﺗ‬ ‫وع‬ ‫ﻧ‬ ‫ﻧد‬ ‫ﻣﺳ‬ KAFO (‫ﺎرات‬ ‫اﻻﺧﺗﺑ‬ ‫ن‬ ‫ﻣ‬ ‫ل‬ ‫ﻟﻛ‬ ‫ﻠﯾﻣﺔ‬ ‫ﺳ‬ ‫ﺔ‬ ‫وﺣﺎﻟ‬ PDF created with pdfFactory Pro trial version www.pdffactory.com