Effect of tibia marker placement on knee joint kinematic analysis.

Area of Science:

• Biomechanics
• Human Movement Analysis
• Orthopedics

Background:

• Multi-site gait analysis research requires reliable kinematic measures across different locations.
• Variability in marker sets can affect the accuracy of joint kinematics.
• Understanding marker set influence is crucial for consistent 3D gait analysis data.

Purpose of the Study:

• To compare knee kinematics derived from different tibial marker sets.
• To assess the impact of marker placement on segmental optimization (SO) and multi-body optimization (MBO) methods.
• To determine the reliability of these methods in multi-site gait analysis.

Main Methods:

• 11 healthy subjects performed level walking with 33 lower extremity markers.
• Four marker set groups on the tibia were analyzed.
• Knee joint kinematics were calculated using SO and MBO, compared via statistical parametric mapping.

Main Results:

• Segmental optimization (SO) showed no significant differences in knee joint angles across marker sets.
• Multi-body optimization (MBO) revealed significant differences in transverse plane knee kinematics with varying marker sets.
• MBO method demonstrated higher sensitivity to marker set variations.

Conclusions:

• The multi-body optimization (MBO) method is more susceptible to variations in marker placement.
• Careful consideration of marker sets is essential for MBO in multi-site 3D gait analysis.
• This finding is critical for accurate data interpretation and clinical decision-making across research sites.