By James CreelSpecial to E4CIf you have already heard of the Jaipur Foot, you are not alone. It is one of the best known prosthetic feet in the world, especially among amputees in developing countries. Prior to the Jaipur Foot, western designs of prosthetic feet were fitted to Indian amputees in the 1960s. It was soon observed that after the initial enthusiasm wore off, the amputees discarded their prostheses and reverted to the use of axillary crutches. User feedback revealed the design did not meet the social and vocational needs of the user or provide the necessary mobility and durability.In light of these unique needs, work commenced to design an appropriate and affordable prosthetic foot. Years of research by a group of eminent orthopedic surgeons and innovative craftsmen led to the Jaipur Foot. It is a non-articulated foot made of three variable density blocks. The hind and forefoot blocks are made of layered microcellular rubber and the ankle block is made of laminated wood with or without a carriage bolt. These blocks are reinforced with tyre cord and encapsulated with a skin-colored cushion compound. The entire structure of the foot is then vulcanized at 120° C and 23 psi.The Jaipur Foot design allows mobility in all three planes, i.e. dorsiflexion/plantarflexion, inversion/eversion, and transverse rotation. It allows amputees to walk, run, squat, climb trees and negotiate uneven and muddy terrain without shoes. The biomechanics and performance of the Jaipur Foot provides users with an affordable natural gait.Today, the Jaipur Foot is internationally popular and has transformed the lives of millions of landmine amputees, and has become “a household name among people who live in the world's many war zones,” the Guardian reports. Jaipur Foot has transcended geographical borders and has been used by more than 400,000 amputees in over 40 countries, which include Afghanistan, Bangladesh, Dominican Republic, Honduras, Indonesia, Iraq, Kenya, Lebanon, Malawi, Mozambique, Nepal, Pakistan, Panama, Philippines and many others, making it the most widely used prosthetic design. Left to right: Yash Narang (MIT), Astha Lalbhai (MSS), Abhilasha Singhvi (MSS), James Creel (ASME), Brad Rogers (ASU), Amos Winter (MIT), Liz Kisenwether (PSU), Mark Henderson (ASU), and Maggie Slattery (PSU). Photo courtesy of James CreelDespite its distinctive features, there are issues relating to standardization, weight reduction and process mechanization that need attention.In 2012, engineers representing Massachusetts Institute of Technology (MIT), Arizona State University (ASU) and Penn State University (PSU) traveled to India to visit the Manav Seva Sannidhi (MSS) prosthetic fitment camp as well as the Bhagwan Mahaveer Viklang Sahayata Samiti (BMVSS) campus facility where the Jaipur Foot is made. These folks had the opportunity to interview doctors, designers, technicians and patients associated with the Jaipur Foot, including the founder of BMVSS, D.R. Mehta and founder and executive trustee of MSS, Abhilasha Singhvi. These conversations helped determine the strengths and limitations of the Jaipur Foot while also establishing design specifications.Two materials, two builds Jaipur Foot is built in one of two ways. There is a handmade rubber model and an injection- molded polyurethane model. The handmade process is remarkable to watch but time consuming. It also poses challenges to uniformity and mass production. However, it lasts users an impressive three to five years. The injection-molded polyurethane version is much easier to manufacture in a uniform manner than the rubber foot. The polyurethane version, however, is not as durable as the handmade version.The mission of these engineers, doctors and designers in India was to combine the durability of the handmade prosthetic with the uniformity of the mass-produced polyurethane version.Research, research, and more research The engineering team laid the groundwork for their redesign By James CreelSpecial to E4CIf you have already heard of the Jaipur Foot, you are not alone. It is one of the best known prosthetic feet in the world, especially among amputees in developing countries. Prior to the Jaipur Foot, western designs of prosthetic feet were fitted to Indian amputees in the 1960s. It was soon observed that after the initial enthusiasm wore off, the amputees discarded their prostheses and reverted to the use of axillary crutches. User feedback revealed the design did not meet the social and vocational needs of the user or provide the necessary mobility and durability.In light of these unique needs, work commenced to design an appropriate and affordable prosthetic foot. Years of research by a group of eminent orthopedic surgeons and innovative craftsmen led to the Jaipur Foot. It is a non-articulated foot made of three variable density blocks. The hind and forefoot blocks are made of layered microcellular rubber and the ankle block is made of laminated wood with or without a carriage bolt. These blocks are reinforced with tyre cord and encapsulated with a skin-colored cushion compound. The entire structure of the foot is then vulcanized at 120° C and 23 psi.The Jaipur Foot design allows mobility in all three planes, i.e. dorsiflexion/plantarflexion, inversion/eversion, and transverse rotation. It allows amputees to walk, run, squat, climb trees and negotiate uneven and muddy terrain without shoes. The biomechanics and performance of the Jaipur Foot provides users with an affordable natural gait.Today, the Jaipur Foot is internationally popular and has transformed the lives of millions of landmine amputees, and has become “a household name among people who live in the world's many war zones,” the Guardian reports. Jaipur Foot has transcended geographical borders and has been used by more than 400,000 amputees in over 40 countries, which include Afghanistan, Bangladesh, Dominican Republic, Honduras, Indonesia, Iraq, Kenya, Lebanon, Malawi, Mozambique, Nepal, Pakistan, Panama, Philippines and many others, making it the most widely used prosthetic design. Left to right: Yash Narang (MIT), Astha Lalbhai (MSS), Abhilasha Singhvi (MSS), James Creel (ASME), Brad Rogers (ASU), Amos Winter (MIT), Liz Kisenwether (PSU), Mark Henderson (ASU), and Maggie Slattery (PSU). Photo courtesy of James CreelDespite its distinctive features, there are issues relating to standardization, weight reduction and process mechanization that need attention.In 2012, engineers representing Massachusetts Institute of Technology (MIT), Arizona State University (ASU) and Penn State University (PSU) traveled to India to visit the Manav Seva Sannidhi (MSS) prosthetic fitment camp as well as the Bhagwan Mahaveer Viklang Sahayata Samiti (BMVSS) campus facility where the Jaipur Foot is made. These folks had the opportunity to interview doctors, designers, technicians and patients associated with the Jaipur Foot, including the founder of BMVSS, D.R. Mehta and founder and executive trustee of MSS, Abhilasha Singhvi. These conversations helped determine the strengths and limitations of the Jaipur Foot while also establishing design specifications.Two materials, two builds Jaipur Foot is built in one of two ways. There is a handmade rubber model and an injection- molded polyurethane model. The handmade process is remarkable to watch but time consuming. It also poses challenges to uniformity and mass production. However, it lasts users an impressive three to five years. The injection-molded polyurethane version is much easier to manufacture in a uniform manner than the rubber foot. The polyurethane version, however, is not as durable as the handmade version.The mission of these engineers, doctors and designers in India was to combine the durability of the handmade prosthetic with the uniformity of the mass-produced polyurethane version.Research, research, and more research The engineering team laid the groundwork for their redesign