Advanced Carbon Fiber Foot Prosthesis : Make In India initiative – A pilot study of the new design

Prosthetics are an example of Assistive Technology (AT) that offer the potential to improve the mobility, quality of life and opportunity of a person with limb loss [1,2]. They are identified as one of the five priority assistive products urgently needed globally. Designed to address India’s high incidence of lower limb amputations and the financial barriers associated with advanced prosthetic devices, we have collaborated with DRDL (Defence Research & Development Laboratary), DRDO (Defence Research & development Organisation, Ministry of Defence, Government of India) to develop an advanced carbon fibre foot that combines durability, functionality, and affordability. The device design has been validated for biomechanical load endurance up to 125 kg with a factor of safety of 2 that promises to revolutionize accessibility by lowering costs. 

(a) Rationale of the study supported by cited literature :

In India, the disability sector, particularly in the context of mobility aids for lower-limb amputees, faces significant challenges. The current market for prosthetics relies heavily on imported solutions, leading to high costs that are unaffordable for a large segment of the population. According to a national survey conducted in 2018, over 7% of individuals with locomotor disabilities are unable to acquire necessary mobility aids due to affordability issues. Of those who do use prosthetics, the vast majority depend on imported devices, which are priced out of reach for many, particularly among lower-income groups.

This proposal, aimed at the development of an indigenous Advanced Carbon Fiber Foot Prosthesis, directly addresses this gap by proposing an affordable, durable, and high-performance prosthetic foot, manufactured in India. By reducing the cost of the prosthetic foot by up to 75% compared to imported models, the project aims to significantly improve accessibility for economically disadvantaged persons with disabilities.

The Indian government’s "Make in India" initiative and its ongoing focus on self-reliance (Atmanirbhar Bharat) align closely with the objectives of this proposal. By developing a locally produced advanced prosthetic foot, the project supports the national agenda of boosting indigenous manufacturing and reducing dependency on foreign imports, particularly in the healthcare and assistive technology sectors.

(a)  Novelty/ Innovation : This is the first made in India Design. So far all the carbon fibre foot prosthetics are imported and this will be the first design to be validated. This would bring down the current cost of product from 1.25 lakhs to 25% or even below as comparable to existing imported products of the same class. By increasing the affordability and functionality of prosthetics, the project can significantly improve the quality of life for amputees and reduce the socioeconomic challenges associated with disability, ultimately fostering greater social integration and economic empowerment.

Demographic and clinical characteristics of the patients including age, body mass index (BMI), comorbidities, education, occupation, stump length (measured from medial knee joint line to the stump edge), duration of amputation and previous prosthetic use, type of prosthetic foot, daily walking time with the prosthesis will be noted.

Functional capacity will be evaluated using the six-minute walking test (6MWT). The 6MWT evaluates walking function and endurance. Patients will be given instructions to walk as much distance as possible along a rectangular path quickly and safely [5,6]

 The intensity of residual limb pain (RLP), sound limb pain (Knee, ankle, Hip – if any) and low back pain will be documented on a Visual Analogue Scale (VAS; from 0 (no pain) to 10 (worst pain)). The socket system, prosthetic foot and overall prosthesis satisfaction, and socket system comfort will be evaluated with a 10-point VAS (from 0 (absolutely dissatisfied) to 10 (absolutely satisfied)).

Level of difficulty experienced during walking on straight path (indoor), walking on uneven path, ascending stairs, descending stairs, ascending ramps and descending ramps will be recorded on a 5-point Likert scale ((1) very easy, (2) easy, (3) neutral, (4) difficult, (5) very difficult).

The QoL of each patient will be assessed using the Short Form-36 (SF-36) at baseline, 3 months, 6 months, 9 months and 12 months. SF-36 consists of 36 questions on eight different subscales that include physical functioning, role limitations due to physical health problems, bodily pain, general health perceptions, energy and fatigue, vitality, social functioning, role limitations due to emotional problems and general mental health. Each subscale of SF-36 will be scored between 0 and 100, and higher scores illustrate better QoL [7]. All the patients will be evaluated with Prosthetic Evaluation Questionnaire (PEQ)(Annexure A) [8,9] at baseline, 3 months, 6 months, and 12 months. At every visit scheduled once in 3 months, documentation of pressure points, discomfort, fatigue wear, and component failure will be analysed by physical inspection and noted. Frequency of visits in between for any discomfort and problems noted by patient and reasons for the same will be documented.

Data Analysis Plan: Mean, median, standard deviation for quantitative outcomes (comfort rating, wear patterns) will be analysed. Baseline vs follow up change in PEQ scores using paired t-tests or Wilcoxon signed-rank test depending on data distribution