Experimental and numerical analyses of alternate materials for performance enhancement of Jaipur foot.

BACKGROUND: The Jaipur foot is the gold standard in low-cost prosthetics, and the amputee population in low-income and middle-income countries has benefited immensely from this innovation. The ability of the Jaipur foot to mimic the behavior of a regular foot, albeit to a limited extent, has made it a popular choice among clinicians and patients. However, the immense popularity has also hindered further research because minimal efforts have been made to investigate the scope of improvement of the Jaipur foot, particularly with new materials. OBJECTIVE: This article focuses on numerical and experimental analyses of various materials for the performance enhancements of the Jaipur foot. METHODS: Contemporary materials are used in finite element analysis to filter the most suitable alternate material for microcellular rubber. The performance of the Jaipur foot fabricated with alternate material is compared with the conventional Jaipur foot through compression testing simulating gait cycle conditions. RESULTS: The EVA foot showed 1-3 mm higher deformation than the MCR foot during the dorsiflexion or heel strike phases, which indicates an appropriate shock absorption and energy storage capacity in heel striking conditions. In forefoot strike phase or plantarflexion, the EVA foot and MCR foot showed identical behavior in deformations. Replacing the MCR with EVA also resulted in reduced weight of the Jaipur foot by 23%. CONCLUSIONS: The weight reduction can help the amputee to expend less energy, thereby improving patient comfort and walking patterns and hence a more natural performance similar to a regular human foot.

Contemporary challenges in clubfoot treatment: A quantitative study among Indian parents.

Purpose: The studies conducted a decade ago showed that the Ponseti method, suffers from many execution-related issues-particularly in low and middle-income countries including poverty, physical distance, lack of transportation etc. The society has undergone many changes, including improvements in literacy, connectivity (both transport and digital), etc., in the last decade. Therefore, this study is designed to identify the contemporary apprehensions, concerns, and challenges of parents seeking CTEV treatment for their child through the Ponseti Method in India. Methods: A descriptive cross-sectional study of 200 parents of the children undergoing treatment at a multi-specialty hospital is carried out using an interview guide. The semi-structured interviews were conducted telephonically and recorded. Results: The statistical analysis shows that a male child is presented late than a female child. The physical distance is associated with child discomfort during the casting and bracing phase, with the travel method affecting the follow-up. The increase in travel time may result in increased casts due to a lack of regular follow-up. Parents' income level is also strongly associated with regularity of follow-up and child discomfort during treatment. Conclusions: The patients traveling long distances in public transport are the most vulnerable group regardless of gender. The children in such cases are more likely to experience discomfort during the casting and bracing phase with a lack of regular follow-up. Expert doctors and brace unavailability in the local area remain vital challenges for the parents.

CAD/CAE of Jaipur foot for standardized and contemporary manufacturing.

Objective: Despite immense popularity of Jaipur foot as low cost prosthetic, not much work has been reported on its design for manufacturing standardization. Without manufacturing standardization, it cannot be mass produced using contemporary manufacturing technologies. The objective of this work is to carry out its computer aided design (CAD) followed by computer aided engineering (CAE) based on the material properties obtained from the previous work [1] of the authors. This may lead to the possible use of modern manufacturing processes for the Jaipur foot design.Design: After modelling using CAD tool including its organic surfaces, the designed foot was analysed using a CAE tool for balanced standing load conditions to determine maximum stresses and deformation in its various parts. The bending analysis was done to check the dorsiflexion movement so that the strained sections could be identified for more reliable and durable prosthetic foot. For the static load analysis, base of the foot was constrained and 300-500 N load was applied through the bolt whereas for bending, the part near the bolt was fixed and pressure was applied at junction of front foot and toes.Results: The results show that the maximum stress and deformation occur at the bolt, while the skin undergoes maximum strain. CAE analysis also proves the robustness of the Jaipur foot design and a well manufactured Jaipur foot as per standardized design should be able to withstand the real life conditions without failure. The CAD model is also used for FDM based printing for a nonfunctional prototype of Jaipur foot.Implications for rehabilitationThe results of this study will serve as an important guideline for further research regarding equivalent material replacement, material optimization and obtaining an optimized design after studying the foot for dynamic analysis.

Assessment of the compressive and tensile mechanical properties of materials used in the Jaipur Foot prosthesis.

BACKGROUND: Designed by Dr. Sethi, the Jaipur Foot prosthesis is ideally suited for amputees in developing countries as it utilizes locally sourced, biodegradable, inexpensive materials and is focused on affordability and functionality. To date, however, no data have been reported on the material properties of the foot components. OBJECTIVES: The goal of this work was to evaluate mechanical properties of the Jaipur Foot components to guide foot design and manufacturing and reduce weight. STUDY DESIGN: Experimental. METHODS: Mechanical testing was conducted on two types of woods (ardu and cheed), microcellular rubber, tire cord, cushion compound, tread compound, and skin-colored rubber. Each material was subjected to testing in either tension or compression based on its location and function in the foot. Samples were tested before and after vulcanization. Two-sample t-tests were used to assess statistical differences. RESULTS: Cheed compressed perpendicular to the grain had a significantly higher modulus of elasticity than ardu ( p < 0.05); however, cheed had a higher density. Vulcanization significantly increased the modulus of skin-colored rubber, cushion compound, and tread compound ( p < 0.05) and decreased the moduli of both microcellular rubber and tire cord ( p < 0.05). CONCLUSION: The material property results from this study provide information for computer modeling to assess material construction on overall foot mechanics for design optimization. Ardu wood was ideal based on the desire to reduce weight, and the tire cord properties serve well to hold the foot together. Clinical relevance With new knowledge on the material properties of the components of the Jaipur Foot, future design modifications and standardized fabrication can be realized, making the Jaipur Foot more available on a global scale.

Epidemiological study of failures of the Jaipur Foot.

OBJECTIVE: The purpose of this study was to examine effects of usage and demographics on damage to the Jaipur Foot prosthesis as well as the epidemiology and etiology of amputations performed at Santokba Durlabjhi Memorial Hospital (SDMH) in Jaipur, India. DESIGN: Total time spent standing, total time spent wearing and total distance walked were compared against severity and location of damage to the prosthesis. Time between initial fitting and follow-up visit for damaged prosthetic was also considered in this analysis. A novel damage severity scale based on prosthesis functionality is presented along with a damage location legend. RESULTS: Patients from 10 different states and two territories throughout India were included in the study. No main effects were found to be statistically significant in predicting severity or location of damage. Only the interaction between a patient's total time spent standing and their total time spent wearing the prosthesis as well as the interaction between a patient's total time spent standing and total distance walked was significant in predicting location of damage to the Jaipur Foot (p = .0327, p = .0278, respectively). CONCLUSIONS: The lack of significant usage factor effect on damage severity or location could support previous findings that lack standardization in materials and manufacturing processes, which is the major drawback of the Jaipur Foot. Implications for Rehabilitation The Jaipur Foot is a safe, reliable and stable product as no abrupt breakage or sudden falls causing injury to the patient were noted. Hence, it is a safe rehabilitation device for lost limbs. The population can squat and sit cross-legged while wearing the prosthetic foot and it does not affect damage severity or location of damage, allowing for these activities to be performed while rehabilitating. The manufacturing of the foot needs to be standardized to improve life of foot. Total time spent standing, total time spent wearing and total distance walked were not predictive of severity or location of damage to the prosthesis, hence providing patient guidelines for activity during rehabilitation.