Temporal parameters estimation for wheelchair propulsion using wearable sensors.

Area of Science:

• Biomechanics
• Rehabilitation Engineering
• Assistive Technology

Background:

• Individuals with spinal cord injury (SCI) depend on upper limbs for wheelchair mobility, leading to high rates of upper extremity pain and injury.
• Accurate monitoring of wheelchair propulsion is crucial for understanding biomechanical load and optimizing rehabilitation strategies for SCI.

Purpose of the Study:

• To evaluate the performance of triaxial accelerometers in estimating temporal parameters of wheelchair propulsion.
• To compare the accuracy of accelerometers placed on the upper arm, wrist, and under the wheelchair.

Main Methods:

• Twenty-six participants with SCI propelled a wheelchair equipped with a SMART(Wheel).
• Triaxial accelerometers were placed on the upper arm, wrist, and under the wheelchair.
• Estimated stroke number and push frequency were compared against video and SMART(Wheel) criteria, using Mean Absolute Error (MAE), Mean Absolute Percentage Error (MAPE), and Intraclass Correlation Coefficients (ICC).

Main Results:

• The upper arm accelerometer demonstrated high accuracy, with MAPE of 8.0% for stroke number and 12.9% for push frequency (ICC: 0.994 and 0.916, respectively).
• Wrist and under-wheelchair accelerometers showed slightly lower accuracy but still reasonable performance.
• The findings indicate good agreement between estimated and criterion measures, particularly for the upper arm placement.

Conclusions:

• Triaxial accelerometers are a viable tool for monitoring temporal parameters of wheelchair propulsion in individuals with SCI.
• Upper arm placement offers the most accurate estimation of stroke number and push frequency, supporting potential clinical and research applications.
• This technology can aid in assessing propulsion patterns, identifying injury risks, and guiding interventions for SCI mobility.