Affiliations: [a] Biomechanics Laboratory, Department of Sport and Movement Sciences, University of Duisburg-Essen, Essen, Germany | [b] Department of Orthopaedic Surgery, St. Josef-Hospital, Ruhr-University Bochum, Bochum, Germany
Correspondence:
[*]
Corresponding author: Marco Hagen, Biomechanics Laboratory, Institute of Sport and Movement Sciences, University of Duisburg-Essen, Gladbecker Str. 182, 45141 Essen, Germany. Tel.: +49 201 183 7386; Fax: +49 201 183 7309; E-mail:marco.hagen@uni-due.de
Abstract:
BACKGROUND: Measuring subtalar joint (STJ) motion is accompanied by
complications due to the oblique STJ axis which results in triplanar
pronation and supination. OBJECTIVE: We developed a pronator and supinator testing apparatus whose
axis was aligned with Inman's STJ axis. The purpose of this study was to
assess day-to-day reliability of active STJ range of motion (ROM)
measurements and to compare the results with those of a rearfoot goniometer. METHODS: Active pronation, supination and total STJ ROM measurements were
administered to 12 men (mean age: 23.8 years) and 12 women (mean age: 22.3 years) at two separate test sessions. Intraclass correlations (ICC), limits
of agreement (LoA) and minimum detectable change (MDC) were calculated. RESULTS: Except for pronation ROM in men, the STJ goniometer revealed
substantial (ICC > 0.8) reliability in all conditions. Relative MDCs and LoAs
were below 15% and 10%, respectively. Significantly higher total ROM
(P< 0.05) was found for women compared to men when using the STJ goniometer.
The rearfoot goniometer showed high reliability (ICCs > 0.7) but
underestimated STJ ROM in average of 37%. CONCLUSIONS: Both goniometric methods showed high day-to-day reliability.
However, when using the rearfoot goniometer, researchers have to consider
whether the level of underestimation of STJ motion is acceptable in the
context of the planned investigation.
Keywords: Range of motion, subtalar joint axis, pronation, supination, intraclass correlations, limits of agreement, minimum detectable change
