Reliability of measurement of knee extensor and flexor muscle peak
torque on the KinCom isokinetic dynamometer in individuals with rheumatoid
arthritis
Affiliations: [a] School of Physiotherapy, The University of Melbourne,
Parkville 3052, Australia | [b] Physiotherapy Department, Royal Melbourne Hospital,
Parkville 3052, Australia
Note: [] Corresponding author: Joan McMeeken, School of Physiotherapy,
The University of Melbourne, Parkville 3052, Australia. Tel.: +61 3 9344 4171;
Fax: +61 3 9344 4188; E-mal: j.mcmeeken@physio.unimelb.edu.au
Abstract: Reliability of measurement of maximum isokinetic muscle performance
in subjects with rheumatoid arthritis has not been reported for the KinCom
dynamometer. The aim in this study was to estimate intra and inter-session
reliability in knee extensor and flexor muscles. Concentric peak torque (Nm) of
knee extension and flexion at 60o.s-1 and 120o.s-1 was measured in 18 subjects
(49.7 +/- 5.3 (29-76) years) with rheumatoid arthritis using a standardised
protocol. Intra-session reliability (ICC 3,1) assessed in six subjects was
found to be high in extensor (0.99) and flexor muscles (0.99). Comparison
between left and right knees showed no statistically significant differences.
Inter-session reliability (ICC 2,3) assessed over a six-week interval was also
high for extensors (60o.s-1 = 0.97, 120o.s-1 = 0.97) and flexors (60o.s-1= 0.94, 120
o.s-1= 0.97). These findings indicate that when using a single rater, inter and
intra-session reliability of knee muscle peak isokinetic concentric torque
measurement are acceptable. The time interval between test sessions of six
weeks reflects the clinical environment. Therefore this protocol provides a
useful test for evaluation of therapeutic interventions directed at the
knee.
