Consistent patient use of the brace is critical to prevent relapse but compliance is difficult to monitor. MiracleFeet wanted Team to help find a way to use connected technology to monitor and assess brace compliance in a practical and cost-effective way that was compatible with the resource available in the low and middle income countries where it operates.
Clubfoot is a birth defect that causes one or both feet to turn inward and upward. The non-surgical Ponseti Method, which has become accepted as the best treatment method, is very easy on the child and effective in 95% of cases. It involves a series of gentle manipulations followed by plaster casts. Following the casts, a foot abduction brace is worn at night and during naps for several years.
We proposed an approach using a low-cost, low-power onboard sensor and connectivity via Bluetooth that is compatible with MiracleFeet’s existing range of braces without changing the fundamental design. The embedded sensor has the potential to allow remote monitoring of brace use and supports effective intervention.
The challenge
The brace is a device made-up of a simple bar and shoes. It is worn for 23 hours a day for the first 3 months after initial treatment and then at night and during naps for the following 4 to 5 years. Bracing is the only statistically significant factor in prohibiting relapse, so this phase of treatment is extremely important.
"The braces come in a range of sizes to fit different age groups and have detachable shoes which clip onto the plastic frame. It was clear we needed to find a monitoring solution that was compatible across all sizes of the brace. It also needed to be low cost, practical and compatible with available communication tools." Alex Gilbert, Managing Consultant, Team Consulting
Monitoring had three clear benefits: early intervention in cases of non-compliance, longer intervals between clinic visits for parents in cases of good compliance and the ability to fully understand the factors behind any relapse in the condition.
Our approach
We understood that the right approach had to fit into the existing brace design, be low-cost and robust. We considered the challenge from several angles: appropriate and effective sensing technologies, power management, mechanical integration, connectivity options and more. To do this, we brought a team together that collectively had all the skills and experience needed and the ability to work effectively across disciplines.
A one-size-fits-all connected solution
The proposed solution was based on keeping the sensing simple using motion and position sensing chips. The device also needed to be miniaturised to allow integration into a secure pocket in the brace that is common to all variants of the brace.
The foot brace also had to provide data storage and communication capabilities via Bluetooth to an app to be used by either the clinician or the caregiver. Our experience in small connected sensors in medical devices enabled us to quickly assess the trade-offs and to find the appropriate solution.
"It is great news to hear that there is a sensor option that is simple, cost-effective and can be done within the current brace design."Christie Pettitt-Schieber, Deputy Director of Programs, MiracleFeet
Software design
"The software design facilitates minimal interaction by a user, allowing them to use the device without changing user behaviour. Data download will be fully automated, occurring at regular intervals and the device can store several months’ worth of data if a connection is not established, or the user does not have access to a suitable mobile device." Thomas Watts, Engineering Consultant, Team Consulting
The mobile app can be designed to work with MiracleFeet’s existing cloud base, adding support for clinics without the need for a complex new system. This allows space for future development of an integrated system.