Reliability of Different Clinical Techniques for Assessing Foot Posture

Area of Science:

• Biomechanics
• Podiatry
• Orthopedics

Background:

• Accurate assessment of foot posture is crucial for diagnosing and managing various musculoskeletal conditions.
• Traditional methods for measuring foot posture, such as navicular drop (NDP) and navicular drift (NDT), and the Foot Posture Index-6 (FPI-6), have varying degrees of reliability.
• Understanding the reliability of these measures is essential for consistent clinical practice and research.

Purpose of the Study:

• To evaluate the interrater and intrarater reliability of navicular drop (NDP), navicular drift (NDT), and the Foot Posture Index-6 (FPI-6).
• To assess the test-retest reliability of the static arch index (SAI) and dynamic arch index (DAI).
• To provide evidence-based recommendations for reliable foot posture assessment methods.

Main Methods:

• Sixty healthy individuals participated in the study.
• Interrater and intrarater reliability were assessed for NDP, NDT, and FPI-6 using digital calipers and the FPI-6 tool.
• Test-retest reliability for SAI and DAI was evaluated using electronic pedography, with all measures repeated after a 5-day interval.

Main Results:

• Intrarater reliability was high for NDP (ICC=0.934-0.970) and FPI-6 (ICC=0.945).
• Interrater reliability was moderate for NDP (ICC=0.712-0.811) and FPI-6 (ICC=0.575).
• Test-retest reliability was good for both SAI (ICC=0.850) and DAI (ICC=0.876).

Conclusions:

• Navicular drop (NDP) demonstrates higher reliability compared to other traditional techniques.
• The Foot Posture Index-6 (FPI-6) exhibits excellent intrarater reliability but only moderate interrater reliability.
• The findings support the use of NDP and FPI-6 for reliable foot posture assessment in clinical and research settings.