Femur loading during gait in newly walking children.

Area of Science:

• Pediatric biomechanics
• Orthopedic research
• Developmental kinesiology

Background:

• Femoral loading is critical for understanding pediatric fracture risk, especially in children with bone fragility.
• Early mobility stages present unique biomechanical challenges, yet femoral loading during this period is understudied.
• Accurate characterization of hip joint loading is essential for clinical assessments.

Purpose of the Study:

• To develop predictive regression models for hip joint loading in newly walking children.
• To quantify 3D hip joint reaction forces and moments during gait in this age group.
• To establish a foundation for subject-specific fracture risk prediction in pediatric populations.

Main Methods:

• Gait and kinetic analyses were performed on children aged 13-23 months.
• Three-dimensional hip joint reaction forces and moments were calculated during walking.
• Regression models were created using subject characteristics (age, height) and walking speed.

Main Results:

• Mean peak resultant hip force was 1.19 N/BW and mean peak resultant hip moment was 0.24 Nm/(BWxL).
• Predictive models achieved high accuracy, with R² values of 0.97 for hip force and 0.94 for hip moment.
• Models effectively correlated age, height, and walking speed with hip loading parameters.

Conclusions:

• Experimental determination of hip joint loading in newly walking children is now feasible.
• Developed regression models offer a non-invasive method for estimating pediatric hip loading.
• These models can be integrated into finite element analysis for personalized fracture risk assessment in children.