Background: Goniometric measurement is currently being used as a diagnostic and outcomes assessment tool for ankle joint dorsiflexion. Despite its common use, its interrater and intrarater reliability has been questioned.
Methods: This is a prospective study examining whether the experience of the examiner or the technique used affects the interrater and intrarater reliability for measuring ankle joint dorsiflexion. Fourteen asymptomatic individuals (8 male and 6 female) with a mean age of 28.2 years (range, 23-52) were enrolled into this study. The years of clinical experience of the five examiners averaged 10.4 years (range, 0-26). Four examiners used a modified Root, Weed and Orien method of measuring ankle joint dorsiflexion. The fifth examiner utilized a nonstandardized technique. A standard goniometer was used for bilateral measurements of ankle joint dorsiflexion with the knee extended and flexed. All five examiners repeated each measurement three times during each of the three sessions, with each session spaced at least 1 week apart.
Results: The interclass correlation coefficient reveals a moderate intrarater and poor interrater reliability in ankle joint dorsiflexion measurements using a standard goniometer. More importantly, further analysis indicates that the use of a standardized technique for measurement of ankle joint dorsiflexion or years of clinical experience does not increase the intrarater or interrater reliability.
Conclusions: The utility of the goniometric measurement of ankle joint dorsiflexion may be limited.