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Updated: Jul 16, 2025
10:07
Measurement of Dynamic Scapular Kinematics Using an Acromion Marker Cluster to Minimize Skin Movement Artifact
Published on: February 10, 2015
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Influence of marker weights optimization on scapular kinematics estimated with a multibody kinematic optimization
F Lefebvre1, I Rogowski2, N Long3
1Univ Lyon, Université Claude Bernard Lyon 1, Laboratoire Interuniversitaire de Biologie de la Motricité, UR 7424, F-69622 Villeurbanne, France; TRINOMA, Villefort, France.
Journal of Biomechanics
|September 12, 2023
Summary
Optimizing marker weights in multibody kinematic optimization significantly improves scapular kinematic estimates. Homogeneous weights on redundant markers are recommended for accurate scapular motion analysis.
Area of Science:
- Biomechanics
- Human Movement Analysis
- Orthopedics
Background:
- Soft tissue artifacts commonly affect scapular kinematic accuracy.
- Improved experimental and numerical methods are needed to enhance scapular motion estimation.
Purpose of the Study:
- To evaluate the impact of marker weighting in closed-loop multibody kinematic optimization on scapular kinematics.
- To determine optimal marker weighting strategies for accurate scapular motion analysis.
Main Methods:
- Fifteen healthy volunteers performed static postures.
- Scapulo-thoracic angles were calculated using a scapula locator reference and multibody kinematic optimization (MKO).
- Marker weights in MKO were optimized to minimize differences from the reference, assessing participant- and movement-specific effects.
Main Results:
- Optimized weighting sets significantly improved scapular orientation accuracy (0.9° to 12.1°, p < 0.0001).
- Optimized weights showed no significant difference compared to homogeneous weights (p = 0.547).
- Optimal weighting sets were found to be participant- and movement-specific.
Conclusions:
- Optimizing marker weights enhances scapular kinematic accuracy in MKO.
- Homogeneous weights on redundant markers (acromion to medial border spine) are recommended for estimating scapular kinematics in upper limb MKO.
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