Article

OBJECTIVE: To compare the reliability of quadriceps-angle (Q-angle) measurements
performed using a short-arm goniometer and a long-arm goniometer and to assess
the accuracy of goniometer-based Q-angle measurements compared with anatomic Q
angles derived from magnetic resonance imaging (MRI). DESIGN: An intra- and
interobserver reliability study. SETTING: University hospital.
Eighteen healthy subjects with no history of knee pain, trauma, or prior surgery
were examined. METHODS: Two physicians, blinded to subject identity, measured Q
angles on both knees of all subjects using 2 goniometers: (1) a short-arm
goniometer and (2) a long-arm goniometer. Q angles were derived from axial MRIs
of the subjects' hip and knees. MAIN OUTCOME MEASUREMENTS: The intra- and
interobserver reliabilities of each goniometer were assessed using the intraclass
correlation coefficient (ICC). The comparison between clinical and MRI-based Q
angles was assessed by using the ICC and a paired t-test. RESULTS: Intra- and
interobserver reliabilities of the long-arm goniometer (intraobserver ICC, 0.92;
interobserver ICC, 0.88) were better than those of the short-arm goniometer
(intraobserver ICC, 0.78; interobserver ICC, 0.56). Although both goniometers
measured Q angles that were moderately correlated to the MRI-based measurements
(ICC, 0.40), the clinical Q angles were underestimated compared with the
MRI-based anatomic Q angles (P < .05). CONCLUSION: The results of this study
suggest that, although reproducible Q-angle measurements can be performed using
standardized patient positioning and a long-arm goniometer, methods to improve
the accuracy of clinical Q-angle measurements are needed.
CI - Copyright (c) 2011 American Academy of Physical Medicine and Rehabilitation.
Published by Elsevier Inc. All rights reserved.

Langue : ANGLAIS