The “Jaipur Foot”

The “Jaipur Foot”

India’s most popular prosthetic for amputees is not the latest in technology, but it’s still the most suitable option for many patients almost 50 years after its development.

It is 8 a.m. on a December morning in Jaipur, Rajasthan, India. The day has just begun at Bhagawan Mahavir Vikalanga Sahayata Samithi (BMVSS), a nonprofit organization dedicated to fitting the disabled with artificial limbs (Figure 1). Slowly, patients from across India and neighboring countries gather in the center’s front yard. By the end of the day, more than 35 people will make a long journey back to their homes and communities outfitted with a new prosthetic leg or arm that will promise them a more active and functional future. The entire treatment is free.

Figure 1: BMVSS in Jaipur, India, is a nonprofit organization dedicated to fitting the disabled with artificial limbs.

Figure 1: BMVSS in Jaipur, India, is a nonprofit organization dedicated to fitting the disabled with artificial limbs.

The Jaipur center, founded in 1975 by Devendra Raj Mehta (Figure 2), is just one of 23 BMVSS centers in India. Since its inception, the organization has outfitted more than 1.45 million amputees around the world with a prosthetic that has become known as the “Jaipur foot” (Figure 3). BMVSS has held more than 50 on-the-spot, limb-fitment camps in 27 countries across the globe, including Afghanistan, Iraq, Honduras, Nepal, Rwanda, Vietnam, and Fiji. The organization has become so successful that it has forged agreements for continuing research and development with Stanford University, the Massachusetts Institute of Technology (MIT), the Indian Space Research Organisation, and the Indian Institute of Technology (IIT), among others.

Figure 2: BMVSS founder Devendra Raj Mehta.

Figure 2: BMVSS founder Devendra Raj Mehta.

Figure 3: The Jaipur foot.

Figure 3: The Jaipur foot.

The Jaipur foot’s popularity is due primarily to the fact that it offers advantages more technically advanced carbon fiber prosthetics cannot. It is sturdy, water resistant, and relatively inexpensive to manufacture (US$50 per prosthetic, compared to US$12,000 in the United States); most importantly, it is uniquely adapted to the needs of its users. Significantly, the prosthetic can be made to fit a patient in as little as a day, and the Jaipur foot lasts the average person around 3.7 years, after which time the patient usually visits one of the centers for replacement. However, depending on usage and environmental conditions, the foot has been known to last much longer.

History and Development

The story of the Jaipur foot can be traced back to 1966, when a team from the World Health Organization visited Sawai Man Singh (SMS) Medical College’s occupational therapy department in Jaipur and met with a group of doctors who were treating amputees. Initially, Indian doctors selected solid-ankle cushioned-heel (SACH) designs from the manufacturer Ottobock in Germany as their prosthetic of choice. It turned out, however, that these were not very useful. They lacked the natural foot’s dorsiflexion action necessary for Indians—especially for rural villagers needing to work on uneven surfaces. Also, Indians often prefer to remain barefoot, lack indoor bathrooms, and squat for religious rituals. For these reasons, the original SACH design was rejected by 80% of patients in early studies.

Figure 4: Master craftsman Ramachandra Sharma, a designer of the Jaipur foot.

Figure 4: Master craftsman Ramachandra Sharma, a designer of the Jaipur foot.

The original Jaipur foot technology was developed in 1968 by a group of eminent doctors at SMS Medical College, led by Dr. Pramod Karna Sethi. Others who served on the design team at the Medical College’s Rajastan Rehabilitation Center were Dr. S.C. Kasliwal, Dr. Mahesh Udawat, and master craftsman Ramachandra Sharma (Figure 4). Sethi asked Sharma to come up with the initial foot design; he created a foot resembling a natural human foot with toes. He opted to use rubber because automobile tires made of rubber are long-lasting and able to take rough roads. Sharma, however, did not know how to use the rubber in a mold. Looking for help, he approached cycle repairer Chugga Bhai who, with his knowledge of vulcanizing and repairing old tires, was able to help Sharma cast the first Jaipur foot using natural rubber. The first person to receive the Jaipur foot did so in 1968. Sharma, at 92, is now retired and lives in Jaipur with his son.

Design and Construction

Figure 5: The Jaipur foot’s construction uses two blocks of microcellular rubber and an ankle section made of lightweight willow wood.

Figure 5: The Jaipur foot’s construction uses two blocks of microcellular rubber and an ankle section made of lightweight willow wood.

Today’s Jaipur foot uses two blocks of microcellular rubber and an ankle section made of lightweight willow wood; the foot also uses nylon cords, which are embedded in the rubber (Figure 5). Additional rubber is used to cover these units and to provide the final form of a human foot, adding flexibility and shock absorption. The external cover uses a cosmetic rubber cushion compound, which gives the prosthetic the color and texture of natural skin.

In 1982, the Jaipur foot team started testing and using EVA polyethylene copolymer for the fabrication of a soft insert and strong high-density polyethylene for a total contact socket that could provide cushioning and shock absorption where the limb is inserted into the prosthetic. These two sections, along with the Jaipur foot and a cuff suspension, complete the prosthesis for dynamic alignment. This unit is several times stronger than a normal human leg and provides mobility close to a natural movement for patients [Figure 6(a)–(c)].

Figure 6: (a) The first step in making a below-knee prosthesis is a plaster of paris mold of the amputee’s stump. (b) A positive of the stump is developed in a lab using the mold. (c) Dr. Praveen Kumar Jain, an orthopedic surgeon, checks an ethylene vinyl acetate insert attached to a high-density polyethylene total contact socket.

Figure 6: (a) The first step in making a below-knee prosthesis is a plaster of paris mold of the amputee’s stump. (b) A positive of the stump is developed in a lab using the mold. (c) Dr. Praveen Kumar Jain, an orthopedic surgeon, checks an ethylene vinyl acetate insert attached to a high-density polyethylene total contact socket.

According to a study published in Prosthetics and Orthotics International comparing the Jaipur foot with the SACH and Seattle foot, although the SACH foot had better shock absorption capacity, the Jaipur foot was more “natural” [1]. A 2003 University of Michigan Business School case study praised the Jaipur foot and the BMVSS for its unique and cost-effective business model [2].

Ongoing Legacy

Because the Jaipur foot has been so successful, the idea of translating its advantages to other types of prostheses became a natural next step. Stanford University has designed a fourbar- linkage polycentric knee joint for above-knee amputees called the Stanford Jaipur knee (Figure 7). The knee has a dynamic center of rotation that varies with knee flexion, thus easily mimicking human knee movement. It is stable during the standing, bending, and swinging phases of leg movement but also allows the user to sit on the floor. The fourth generation of this knee is currently being used at BMVSS, and 7,500 have been fitted to patients in India with excellent results. The knee costs US$20 to manufacture in India. Stanford University is also currently working with BMVSS to develop an artificial hand called the Jaipur hand, which will be in field trials soon. Currently, there are also three projects underway with MIT to develop a wheelchair and hand-pedaled tricycle for rural conditions, a braking knee joint, and a new foot piece.

Figure 7: Dr. Pooja Mukul (right) is shown with Kulviner Singh, from Amritsar, Punjab, India, who is fitted with a fourth-generation Stanford Jaipur knee and a Jaipur foot.

Figure 7: Dr. Pooja Mukul (right) is shown with Kulviner Singh, from Amritsar, Punjab, India, who is fitted with a fourth-generation Stanford Jaipur knee and a Jaipur foot.

The Indian Space Research Organization and four IIT branches are working on new designs and materials for improving the performance of the prosthesis. This research, using polyurethane, is expected to bring down the weight of the Jaipur foot from its current 850 g. BMVSS has set up a state-of-the-art gait research center at the BMVSS campus in Jaipur named after German philanthropist and publisher Paul Hamlyn that is supported by the U.K. Foundation and the Indian Railway Catering and Tourism Corporation. These developments promise further improvements to the performance and life span of the Jaipur foot.

According to Mehta, even though the first Jaipur foot was fabricated in 1968, it took seven years to fit the first 50 limbs and the next seven years to reach the first 10,000 limbs. Today, each year around 65,000 people around the world benefit from the Jaipur foot (Figure 8), which won out early on over several other early prostheses, including the Madras foot and Muller foot. Mehta says the key to its success has been the BMVSS center. Overhead is kept below 4% of the total cost of the operation, allowing the center to provide prostheses and other supports, such as food and accommodation, to patients totally free. The trust receives funding through donations from individuals and institutions, including the Indian government. A number of corporations provide funding under the new Corporate Social Responsibility Act of India, which mandates that private firms donate 2% of their profits for social work.

Figure 8: Sudhama Ray, a below-knee amputee, demonstrates squatting with a Jaipur foot. He lost his left leg in a railway accident in 1984 in Kolkata, West Bengal, India, and was fitted with a Jaipur foot in 1988. He now makes artificial legs for others at the BMVSS workshop.

Figure 8: Sudhama Ray, a below-knee amputee, demonstrates squatting with a Jaipur foot. He lost his left leg in a railway accident in 1984 in Kolkata, West Bengal, India, and was fitted with a Jaipur foot in 1988. He now makes artificial legs for others at the BMVSS workshop.

Although the Jaipur foot is nearly 50 years old, ironically, in this high-tech age, it remains the most well-used and wellloved prosthetic in many regions of the world. A relatively simple tool continues to make a huge difference for needy and disadvantaged amputees in India and across the globe.

References

  1. A. P. Arya, A. Lees, H. C. Nirula, and L. Klenerman, “A biomechanical comparison of the SACH, Seattle and Jaipur feet using ground reaction forces,” Prosthet. Orthot. Int., vol. 19, no. 1, pp. 37–45, Apr. 1995.
  2. S. Macke, R. Misra, and A. Sharma, Jaipur foot: Challenging convention, Case Study Series, Univ. Michigan Bus. School, Ann Arbor, MI, 2003. [Online].