Improved design and development of a functional moulded prosthetic foot

Abstract

Purpose: In the Indian scenario, the Jaipur foot is a low-cost breakthrough that enabled the disabled person to adapt to the Indian environment. The aim of this study is to modify the present foot in terms of ankle support design and method of fabrication, foot moulds profile and the inner core material in order to improve the performance and durability. Method: The optimized design of ankle support and flat foot profile moulds suitable for both left and right foot were developed through CAD/CAM and prosthetic feet were fabricated using ethylene vinyl acetate (EVA) foam as an appropriate alternative core material for microcellular rubber (MCR). The developed prosthetic feet were tested for rigidity by load-deflection analysis in universal testing machine. Result: EVA foot had shown better rigidity than conventional MCR foot, which will help in weight transfer during walking and increase the durability. The CAD modeled ankle support and single block EVA had made the manufacturing process easy and reduced the weight of foot and improved Gait to the person fitted with it due to improved flat foot profile. Conclusion: The new artificial foot had proven to be efficacious technically as well as functionally, which is clearly borne out from the extremely positive feedback given by the amputees.

Implications of Rehabilitation

• Persons with below knee amputation are usually provided with transtibial prosthesis, which allows for easier ambulation and helps them to get back to their normal life.

• Transtibial prosthesis is an artificial limb that replaces a lower limb that is amputated below the knee.

• In our study, a new prosthetic foot with a modified ankle support and flat foot profile using better inner-core material than the conventional Jaipur foot was developed and the process was also optimized for mass production. The developed prosthetic foot can be fitted with both above and below knee exoskeleton type of prosthesis.

• Ankle support
• below knee amputation
• CAD/CAM
• ethylene vinyl acetate
• Jaipur foot
• microcellular rubber
• prosthetic foot

Acknowledgements

Authors thank RuTAG, Indian Institute Technology Madras, Chennai and Kasturba Hospital, Gandhigram Trust, Tamil Nadu, India, for product development and field trial studies.

Declaration of interest

The authors report no declarations of interest.