Intrarater test-retest reliability of hip range of motion and hip muscle strength measurements in persons with hip osteoarthritis.
OBJECTIVE
To examine the relative and absolute intrarater test-retest reliability of muscle strength and range of motion (ROM) measurements of the hip performed in people with hip osteoarthritis.


METHODS
Repeated measures.


METHODS
Human movement laboratory of a university.


METHODS
Participants (N=22; 10 men, 12 women; age range, 50-84y) with hip osteoarthritis.


METHODS
On 2 separate occasions, at least 1 week apart, isometric torque measurements were obtained from the hip rotators, flexors, abductors, and extensors. Passive ROMs in hip rotation, flexion, abduction, and extension were also determined.


METHODS
Relative reliability was estimated using the intraclass correlation coefficient, model 2,2 (ICC(2,2)). Absolute reliability was estimated using the coefficient of variation (CV) and the standard error (SE) of measurement.


RESULTS
For measurements of muscle strength, ICC(2,2) ranged from .84 to .97, and the CV ranged from 8% to 15.7%. Hip extensors and internal and external rotators showed high ICC(2,2) (>.96) and low CV (<9.8%); hip abductors showed the lowest ICC(2,2) (.84) and the highest CV (15.7%). For ROM measurements, ICC(2,2) ranged from .86 to .97 and SE ranged from 3.1 degrees to 4.7 degrees . Hip flexion ROM showed the highest ICC(2,2) (.97) and an SE of 3.5 degrees ; hip extension ROM showed the lowest ICC(2,2) (.86) and the highest SE (4.7 degrees ).


CONCLUSIONS
Strength and ROM testing of the hip in people with hip osteoarthritis can be performed with good to excellent reliability.
Pua
Yong-Hao
YH
Center for Health, Exercise and Sports Medicine, School of Physiotherapy, University of Melbourne, Melbourne, Australia. y.pua@pgrad.unimelb.edu.au
Wrigley
Tim V
TV
Wrigley
Tim W
TW
Cowan
Sallie M
SM
Bennell
Kim L
KL
D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006621:Hip Joint / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction / Q000502:physiology; D053580:Muscle Strength / Q000502:physiology*; D053581:Muscle Strength Dynamometer; D015207:Osteoarthritis, Hip / Q000503:physiopathology*; D016059:Range of Motion, Articular / Q000502:physiology*; D015203:Reproducibility of Results; D019415:Torque