Plantar Pressure Assessment: A New Tool for Postural Instability Diagnosis in Multiple Sclerosis - Technologies for Medical Sciences - page 189

Tabl e 1 Demographic, anthropometric and clinical characteristics of study
population

Mean ˙ S.D. (Range)

Variable MS Subjects N D 29 Healthy Subjects N D 28

Age (years) 43,2 ˙ 12,1 (20-63) 36,8 ˙ 8,96 (19-62)

Gender 17 females; 12 males 19 females; 9 males

Ratio 1.4:1 2.1:1

Foot Size a 39,2 ˙ 2,48 (35-43) 38,5 ˙ 2,57 (35-44)

Berg balance scale 46,6 ˙ 9,97 (21-56) 55,7 ˙ 0,47 (55-56)

Disease duration (years) 8,72 ˙ 6,18 (0,17-22) -

a Foot size in continental European system (adults)

normal gait. The midgait protocol requires higher space and time to perform the
tests, due to a larger number of steps and the effect of “target”. This “Targeting
Effect” is considered the necessary adjustments to perform a accurate contact on
the plate surface [ 95 ]. According to some authors [ 96 ], the 1step protocol and 2
step protocol do not show significant differences in peak pressure and pressure-
time integral when compared to 3-step protocol. The same study also concluded
that the 1 step protocol provides a higher confidence in the register of plantar
pressure when compared with the 3-step protocol. The variability in 1 and 2 steps
protocol may be affected, because in these methods, the pressure is evaluated during
gait initiation, which is considered a instability phase, defying the control system
until the stabilization is acquired [ 97 ]. Moreover, the abbreviated protocols are not
representative of steady gait, but reduce the number of eliminated trials due to the
“target” effect, so they are widely used. There are no comparative studies of these
protocols in MS patients. The validity and confidence in the register of plantar
pressure in this population, remains unknown. However, there are studies in this
population that used the 1 step protocol [ 98 , 99 ]. In our study, we used the 1 step
protocol based on the participant's safety, and to minimize any fatigue effects.

3.5 Statistical Analysis

Statistical analysis was performed using the software Statistical Package for the
Social Sciences (SPSS), version 17.0 software for Windows XP SP2 (SPSS,
Chicago, IL, USA) and Microsoft ® Excel 2003. We calculated Spearman correlation
coefficients to evaluate the validity of the postural stabilization parameters for the
considered population of MS subjects.
Demographic, anthropometric and clinical characteristics (mean, standard devi-
ation and range) for all subjects are listed in Table 1 .