Reliability of doming and toe flexion testing to quantify foot muscle strength

Area of Science:

• Biomechanics
• Musculoskeletal research
• Clinical assessment tools

Background:

• Quantifying intrinsic foot muscle strength presents a challenge for clinicians and researchers.
• Accurate measurement is vital for assessing weakness linked to foot and lower leg functional issues, such as plantar fasciitis and hallux valgus.
• This study introduces three novel methods for measuring foot strength: doming, hallux flexion, and lesser toe flexion.

Purpose of the Study:

• To develop and validate novel, reliable methods for assessing intrinsic foot muscle strength.
• To establish the reliability of three new strength tests (doming, hallux flexion, lesser toe flexion) in healthy volunteers.
• To provide clinicians and researchers with practical tools for evaluating foot muscle function.

Main Methods:

• Twenty-one healthy volunteers participated in two testing sessions separated by one to five days.
• Participants performed novel strength tests (doming, hallux flexion, lesser toe flexion) multiple times with different raters and sessions.
• Intra-class correlation coefficients (ICCs) were calculated to assess inter-rater, inter-day, and intra-rater reliability.

Main Results:

• All three novel foot strength tests demonstrated good to excellent reliability across different raters, days, and sessions.
• Average doming strength was 99.96 ± 47.04 N.
• Average hallux flexion strength was 65.66 ± 24.5 N, and average lateral toe flexion strength was 50.96 ± 22.54 N.

Conclusions:

• The developed doming, hallux flexion, and lesser toe flexion tests are reliable and simple to implement.
• These low-cost methods are suitable for both clinical practice and research settings.
• For optimal reliability in repeated testing, it is recommended that the same researcher or clinician conducts the assessments.