Article

OBJECTIVE: To establish the stability reliability, precision, and minimum value
for detecting real differences for quadriceps angle (Q-angle) measurements based
on standardized protocols and surface goniometry. DESIGN: An intratester
reliability study. SETTING: University research laboratory. PARTICIPANTS:
Fifty-two healthy, young, relatively lean adults (25 men and 27 women) from the
university community with no history of knee injury. METHODS: Q-angle was
assessed with surface goniometry on 2 separate occasions separated by 48 hours.
Subjects assumed a supine position with: (1) extended hips and knees, (2) neutral
hip rotational position, (3) neutral foot position, and (4) isometrically
contracted quadriceps femoris muscles. The axis of a manual extendable-arm
goniometer was placed over the center of the right patella with the proximal arm
situated over the anterior-superior iliac spine and the distal arm over the
center of the tibial tuberosity. MAIN OUTCOME MEASURES: Stability reliability was
calculated with use of intraclass correlation (ICC, 2-way random model) and
precision was calculated by standard error of measurement (SEM). The 95% limits
of agreement also were calculated to estimate the minimum detectable difference
in Q-angles. The lowest acceptable ICC was set at >/=0.70 for stability
reliability. RESULTS: The following ICC (SEM) values were found: all subjects =
0.88 (1.0 degrees ), men = 0.77 (1.0 degrees ), and women = 0.85 (1.0 degrees ).
The 95% limits of agreement were 3 degrees for the same 3 groups. CONCLUSIONS:
The surface goniometry protocol described herein appeared to be reliable for
relatively lean young men and women. Although measures were precise to 1.0
degrees , it appears a difference of 3 degrees may be needed to detect a real
difference in Q-angles when measured in this fashion.
CI - Copyright (c) 2013 American Academy of Physical Medicine and Rehabilitation.
Published by Elsevier Inc. All rights reserved.

Langue : ANGLAIS