Reliability of stabilised commercial dynamometers for measuring hip abduction strength: a pilot study

Background: Reliable quantification of hip abductor strength in a clinical setting is challenging. Objectives: To examine the intrarater and interrater reliability of three commonly used commercial dynamometers in the measurement of hip abduction. Methods: Supine gravity minimised measures of unilateral hip abduction strength were recorded in 10 women (mean (SD) age 23.5 (1.9) years) using three different commercially available dynameters. Measurements were repeated over a three day period with a different device used on each day. Results: Intrarater reliability ranged from 0.880 to 0.958 across the three devices, and measures of interrater reliability ranged from 0.899 to 0.948. Conclusion: Commercially available dynamometers can be used to quantify hip abduction strength with good to excellent reliability. A previously undescribed method of quantifying hip abduction strength in a clinical setting using readily available instrumentation is presented.