Detecting spinal posture change in sitting positions with tri-axial accelerometers

Area of Science:

• Biomedical Engineering
• Rehabilitation Technology
• Biomechanics

Background:

• Accurate monitoring of spinal posture is crucial for understanding and managing musculoskeletal health.
• Existing methods for posture assessment can be cumbersome or lack precision.
• Wearable sensor technology offers a potential solution for objective and continuous posture evaluation.

Purpose of the Study:

• To introduce and validate a method for monitoring postural changes in a sitting position using tri-axial accelerometers.
• To assess the precision and reliability of tri-axial accelerometers for measuring spinal posture.
• To compare accelerometer-based measurements with a gold-standard motion analysis system.

Main Methods:

• Three tri-axial accelerometers were utilized to capture trunk movements during specific postural changes (forward flexion, lateral bending).
• A motion analysis system and a 3D rotation alignment device served as the reference standard for validation.
• Static calibration and dynamic sitting posture measurements were performed.

Main Results:

• Static calibration demonstrated high precision and reliability with Root Mean Square (RMS) error <= 1 degree and Intraclass Correlation Coefficient (ICC) of 1.000.
• For sitting postures, the average RMS difference between accelerometers and the motion analysis system was <= 5 degrees on coronal and sagittal planes.
• The system showed good agreement with the motion analysis system across various sitting postures.

Conclusions:

• Tri-axial accelerometers provide a precise and reliable method for monitoring spinal postural changes.
• This technology is suitable for tracking posture on the sagittal and coronal planes in sitting positions.
• Accelerometer-based systems offer a viable tool for objective postural assessment in clinical and research settings.