Reliability and Validity of Isometric Knee Extensor Strength Test With Hand-Held Dynamometer Depending on Its Fixation: A Pilot Study.
- Author:
Won Kuel KIM
1
;
Don Kyu KIM
;
Kyung Mook SEO
;
Si Hyun KANG
Author Information
- Publication Type:Original Article
- Keywords: Muscle strength dynamometer; Isometric contraction; Physical restraint; Dimensional measurement accuracy; Knee joint
- MeSH: Dimensional Measurement Accuracy; Female; Humans; Isometric Contraction; Knee Joint; Knee*; Leg; Methods; Muscle Strength Dynamometer; Pilot Projects*; Reproducibility of Results*; Restraint, Physical; Supine Position; Tibia; Torque; Volunteers
- From:Annals of Rehabilitation Medicine 2014;38(1):84-93
- CountryRepublic of Korea
- Language:English
- Abstract: OBJECTIVE: To determine the reliability and validity of hand-held dynamometer (HHD) depending on its fixation in measuring isometric knee extensor strength by comparing the results with an isokinetic dynamometer. METHODS: Twenty-seven healthy female volunteers participated in this study. The subjects were tested in seated and supine position using three measurement methods: isometric knee extension by isokinetic dynamometer, non-fixed HHD, and fixed HHD. During the measurement, the knee joints of subjects were fixed at a 35degrees angle from the extended position. The fixed HHD measurement was conducted with the HHD fixed to distal tibia with a Velcro strap; non-fixed HHD was performed with a hand-held method without Velcro fixation. All the measurements were repeated three times and among them, the maximum values of peak torque were used for the analysis. RESULTS: The data from the fixed HHD method showed higher validity than the non-fixed method compared with the results of the isokinetic dynamometer. Pearson correlation coefficients (r) between fixed HHD and isokinetic dynamometer method were statistically significant (supine-right: r=0.806, p<0.05; seating-right: r=0.473, p<0.05; supine-left: r=0.524, p<0.05), whereas Pearson correlation coefficients between non-fixed dynamometer and isokinetic dynamometer methods were not statistically significant, except for the result of the supine position of the left leg (r=0.384, p<0.05). Both fixed and non-fixed HHD methods showed excellent inter-rater reliability. However, the fixed HHD method showed a higher reliability than the non-fixed HHD method by considering the intraclass correlation coefficient (fixed HHD, 0.952-0.984; non-fixed HHD, 0.940-0.963). CONCLUSION: Fixation of HHD during measurement in the supine position increases the reliability and validity in measuring the quadriceps strength.