Assessing 3D paediatric foot morphology using low-dose biplanar radiography: Parameter reproducibility and...

Area of Science:

• Paediatric orthopaedics
• Medical imaging
• Biomechanical analysis

Background:

• Traditional physical examination and weight-bearing radiography for foot and lower limb assessment are subjective and prone to bias.
• Low-dose biplanar radiography (LDBR) shows promise for pediatric lower limb evaluation but lacks foot assessment capabilities.
• Current methods for paediatric foot assessment are limited in providing comprehensive 3D weight-bearing data.

Purpose of the Study:

• To develop and validate a novel 3D radiographic analysis method for the paediatric foot using LDBR.
• To determine the reproducibility of anatomical landmarks identified via LDBR in paediatric feet.
• To report reference values for calculated radiographic parameters of the paediatric foot.

Main Methods:

• Two biplanar radiographs were acquired simultaneously using the EOS system in 10 healthy children.
• Two observers performed three 3D reconstructions per foot to assess measurement uncertainty and landmark reproducibility.
• Standard error of reproducibility and 95% confidence intervals were calculated for anatomical landmarks and clinical parameters.

Main Results:

• High reproducibility was observed for key anatomical landmarks, including calcaneal pitch angle and tibio-calcaneal angle (95%CI < 5%).
• The study reports the measured values for these angles in the paediatric population.
• The developed LDBR-based method demonstrated reliable 3D reconstruction of the paediatric foot.

Conclusions:

• The novel LDBR-based radiographic method offers a reproducible means for 3D paediatric foot analysis.
• This technique facilitates the development of new parameters for describing 3D foot morphology.
• It enables simultaneous assessment of the lower limb and foot in a weight-bearing position.