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Is an ellipsoid surface suitable to model the scapulothoracic sliding plane?
Y Blache1, F Lefebvre2, I Rogowski1
1Univ Lyon, Université Claude Bernard Lyon 1, Laboratoire Interuniversitaire de Biologie de la Motricité, EA 7424, F-69622 Villeurbanne, France.
Journal of Biomechanics
|February 14, 2024
Summary
This study found that an ellipsoid surface can effectively model the scapulothoracic sliding plane for kinematic analysis. Optimal calibration requires only five poses, reducing experimental costs.
Area of Science:
- Biomechanics
- Human Movement Analysis
- Orthopedics
Background:
- Closed-loop kinematic chains are used for scapular kinematics.
- Current ellipsoid calibration methods are inconsistent.
Purpose of the Study:
- To determine if an ellipsoid surface can model the scapulothoracic sliding plane.
- To find the optimal number of static poses for ellipsoid calibration.
Main Methods:
- Inserted pins with markers into scapular spines of two males.
- Recorded various arm movements.
- Calibrated ellipsoid parameters using different numbers of movement frames.
Main Results:
- Ellipsoid radii varied significantly across directions and participants.
- Minimal increase in scapula-to-ellipsoid distance with reduced calibration frames (five poses).
- Participant- and movement-specific calibration yielded accurate modeling.
Conclusions:
- Ellipsoid surfaces can model the scapulothoracic sliding plane effectively.
- Five poses are sufficient for accurate ellipsoid calibration.
- This approach reduces experimental time and cost.
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