Validity of Arch Height Measuring Tool in Comparison with Chippaux- Smirak Index and Staheli’s Arch Index: A Pilot Study

Abstract

Background: Flat foot is a postural deformity also known as pes planus is a condition where the arches of the
foot collapse and the entire sole comes into contact with the ground when standing. Various tools are available
to measure the extent of flatfoot which involves the usage of inks, dyes, expensive instrumentation, etc., which
may be harmful and not available at all times. The arch height measuring tool is portable, easy to use, inexpensive
and quick. However, the validity of this tool for flat foot is unknown and hence the objective of the study was to
identify the same.
Objective: To determine the validity of the ‘Arch Height Measuring Tool’ designed by E-Soles Custom Footbeds
as compared to Chippaux-Smirak Index and Staheli’s Arch Index.
Methods: The medial longitudinal arches of the feet of 30 children with neurodevelopmental delay were assessed
with static footprints evaluated using Staheli’s Arch Index, Chippaux-Smirak Index and also using The Arch
Height Measuring Tool. The footprints were classified into flatfoot and non-flatfoot and further subjected to data
analysis.
Results: The tool when compared with the Chippaux-Smirak Index and Staheli’s Arch Index was found to have
a sensitivity of 30% and 28.3% respectively, specificity of 41.6% and 25% respectively and an accuracy of 72% and
75% in detecting flat feet in children with neurodevelopmental delay (NDD).
Conclusion: The study concludes that the Arch Height Measuring Tool with its current classifications is not
suitable for diagnosing mild flatfeet due to the higher false negative results.