Student designs game-changing device for people with lower limb impairments

Toi Rauwhārangi College of Creative Arts (CoCA) Bachelor of Design with Honours alumnus George Philp chose to study design due to his love for making things and a desire to help people.

For his final-year industrial design project, he created Leg-Up, a thoughtfully-designed custom-fit Knee Ankle Foot Orthosis (KAFO) that could transform the landscape of mobility assistance.

Leg-Up challenges the conventional image of orthotics as mere medical devices. Instead, it positions itself as a desirable and accessible enabler of fully independent mobility, helping those with lower limb impairments stand tall and interact with the world on their own terms.

The thought process behind the design

By leveraging semi-autonomous parametric design and manufacture, Leg-Up shifts orthotics from being a medical device and signifier of disability to an accessible, desirable enabler of fully independent mobility.

George says he was inspired to design Leg-up because it gave him a chance to make a positive difference in people's daily lives.

"A lecturer of mine would often say 'use your design powers for good'. I felt that helping a group of people to stand up who are often overlooked was a good start."

The World Health Organization (WHO), tells us that disability affects diverse groups of people; it is part of being human and integral to human experience. Globally, 16 per cent of the population live with or have experienced a significant disability. People living with disability, however, die earlier, have poorer health and experience more limitations and discrimination in everyday life.

George says the market for assistive aids and mobility solutions for impaired people is large and expansive. A common theme in the design of solutions in this area is compromise:

• One size should fit all
• Trading off aesthetics for basic functionality
• Manufacturability over usability
• Adjustability for size ranges over customisation for individuals.

"The gold standard of mobility is the wheelchair. On the surface it provides low energy input, diverse acceptance, relatively fast transportation and an existing infrastructure of understanding and acceptance. From the user’s perspective it’s not as easy, as it requires a degree of skill and practice to navigate the public domain. Gutters and steps are often impassable or discriminatory," George says.

"The world is set up for standing interactions and navigation. For those who don’t have full use of their legs, being able to stand up has significant advantages, including being able to use public transport and facilities, navigate the built environment, socialise naturally, talk eye to eye and give or receive standing hugs."

Knee Ankle Foot Orthosis (KAFO) provide structural support for lower limb disability. More specifically, KAFOs provide postural support for standing and the correct gait for walking. There are several types of KAFO devices, with various degrees of articulation and performance. Like most orthotic devices, they come with a range of logistic and usability challenges including:

• Discomfort - from pressure sores, breathability, fit and adjustability
• Poor user experience - difficulties in putting on and taking off, strap tension adjustment
• Stigma – poor aesthetic qualities in entry level models, another marker of disability
• Accessibility – high costs, clinics providing orthotic services are few and far between, with long wait times, and a long and involved fitting process.

Features of Leg-Up

By addressing the above challenges, Leg-Up mitigates issues of usability and proximity to orthotic support. To do this, an integrated strategy dealing with product features, performance, elevated levels of usability and design, customisation and access to and speed of fitment and delivery was developed.

By integrating modern digital tools and fabrication technologies, individual clients of orthotic services can be scanned remotely with contemporary smartphones using technology available through a wide range of commonly available apps. The phone camera splices photos or video into accurate 3D representations of a client's leg.

This data is then translated by the orthotics service, integrating into design software for semi-autonomous development, scaling and customisation from preferences the client has supplied. With the parametric placement of strapping and latch features added, the design is sent to additive manufacture for the main component builds.

Components are returned to the orthotics service for assembly. Fit trials and initial assessment can be done online, or with local service agents such as occupational therapists, physiotherapists or outpatient services.

This rapid development significantly democratises the access to sparse orthotics services. As a systems product, Leg-Up can be readily serviced, updated for changing leg shape over time and can have aesthetic features updated to the client’s requirements.

Perforations in support components ensure breathability and reduce weight. The customer's specification of these perforation details will provide individuals with the ability to refine the design of Leg-Up in line with their own preferences.

The design includes an off-centre cam and hook latch with interchangeable strapping to provide secure location to the limb. Boa-type ratchet buckles provide refined individual adjustment for comfort. Comfort and usability are substantially improved, with the combination of elastic strap and ratchet boa buckle allowing the brace to be loosened for comfort while staying in place, meaning single-handed adjustment can be achieved.

Leg-Up provides benefits to the end users beyond product design. It is a modern, tech-savvy product that allows users to stand and meet the world on their terms.

Also published on Medtech-iQ Aotearoa.