Ground Contact Time Estimating Wearable Sensor to Measure Spatio-Temporal Aspects of Gait

Area of Science:

• Biomechanics
• Rehabilitation Engineering
• Wearable Technology

Background:

• Inpatient gait analysis is crucial for foot amputee rehabilitation, focusing on ground contact time (GCT) differences.
• Current methods rely on limited in-clinic assessments, hindering continuous monitoring and remote diagnosis.
• Accurate GCT measurement is essential for providing effective gait improvement advice.

Purpose of the Study:

• To present Suralis, a wearable sensor system for gait analysis in foot amputees.
• To develop and validate algorithms for detecting initial contact (IC) and toe-off (TO) events for GCT calculation.
• To enable continuous feedback and remote diagnosis of gait behavior using reliable, real-world data.

Main Methods:

• Developed a wearable system (Suralis) integrating an inertial measurement unit (IMU) and a pressure-measuring sock.
• Implemented and validated algorithms for IC and TO event detection to determine GCT difference.
• Conducted two data acquisitions with able-bodied individuals and prosthesis wearers for algorithm testing.

Main Results:

• Algorithms demonstrated median GCT errors of -51.7 ms (IMU) and 14.7 ms (sensor sock) compared to ground truth.
• The validated algorithms provide a suitable basis for wearable gait analysis.
• The Suralis system effectively calculates GCT difference, a key component of gait analysis.

Conclusions:

• The Suralis wearable system offers a viable solution for continuous, real-world gait analysis.
• It facilitates remote diagnosis of spatio-temporal gait aspects for amputee rehabilitation.
• This technology empowers patients with continuous feedback for improved gait management.