Effect of orthoses on postural stability in asymptomatic subjects with rearfoot malalignment during a 6-week acclimation period.
OBJECTIVE
To determine the effect of custom-fitted orthoses on postural sway over a 6-week acclimation period.


METHODS
Repeated-measures analysis of variance on postural sway measures with factors being group (control, malaligned), time (initial, 2 wk, 4 wk, 6 wk postintervention), and condition (with orthoses, without orthoses). For single-limb stance, side (right, left) was analyzed to determine bilateral differences.


METHODS
Biodynamics laboratory.


METHODS
Twenty-one subjects, 11 asymptomatic with rearfoot malalignment and 10 asymptomatic with normal rearfoot alignment.


METHODS
Orthoses were prescribed and worn for 6 weeks. Balance testing was performed on 4 different dates with each subject tested in both orthotic conditions. Postural control was measured with three 10-second eyes-closed trials for single-limb stance, one 20-second eyes-closed bilateral stance with the platform moving, and one 20-second eyes-open bilateral stance with the platform and surroundings moving.


METHODS
Sway velocity (in deg/s) for single-limb stance and equilibrium score for bilateral stance.


RESULTS
Postural sway measures were significantly decreased during single-limb testing with orthoses versus without orthoses, regardless of group. The orthotic intervention significantly improved bilateral stance equilibrium score in the malaligned group at weeks 2, 4, and 6 when compared with measures at the initial week. Equilibrium score of the malaligned group with orthoses at initial week was significantly lower (worse) than the control group with orthoses at initial week; however, these results were not repeated during measurements taken at weeks 2, 4, or 6.


CONCLUSIONS
The application of orthoses decreased sway velocity for single-limb stance, improving postural stability regardless of group when visual feedback was removed. During bilateral stance, postural stability was initially worse for the malaligned group with and without orthoses when compared with the control group; however, improvements were seen by week 2 and continued throughout the remainder of testing. Clinically, the application of orthoses appears to improve postural control in people with rearfoot malalignment, particularly when vision is removed.
Mattacola
Carl G
CG
Division of Athletic Training, College of Health Sciences, University of Kentucky, Lexington, KY 40536-0200, USA. carlmat@uky.edu
Dwyer
Maureen K
MK
Miller
Amy K
AK
Uhl
Tim L
TL
McCrory
Jean L
JL
Malone
Terry R
TR
D000222:Adaptation, Physiological; D000328:Adult; D017760:Bone Malalignment / Q000503:physiopathology*; D002111:Calcaneus / Q000503:physiopathology; D005260:Female; D006365:Heel / Q000503:physiopathology*; D006801:Humans; D008297:Male; D009989:Orthotic Devices; D004856:Postural Balance