Table 1

Descriptive statistics
Standard shoes Orthopaedic shoes
N = 25 A. Mean (SD) Confidence interval B. Mean (SD) Confidence interval Relative change T-test (p)
Step frequency (Hz) 1.76 (0.18) 1.69–1.82 1.76 (0.17) 1.70–1.82 0.0% 0.51
ML 0.70 (0.15) 0.64–0.76 0.63 (0.10) 0.59–0.67 -10% 0.00
Dynamic stability (λ*) V 0.71 (0.14) 0.65–0.76 0.65 (0.11) 0.60–0.69 -9% 0.03
AP 0.64 (0.15) 0.58–0.70 0.60 (0.08) 0.56–0.63 -7% 0.04

Values are expressed as mean (N = 25), Standard Deviation (SD) and 95% Confidence Interval (mean ±1.96 times the Standard Error of the Mean). Relative change is the average percentage of change induced by orthopaedic shoes (i.e. column B minus column A divided by column A). The t-test column shows the p values of paired t-tests. Step frequency is the number of steps per second (walking cadence). Dynamic stability is defined as the logarithmic rate of divergence in the acceleration signals (finite time Lyapunov exponent, λ*). ML, V and AP stand for respectively Medio-Lateral, Vertical and Antero-posterior accelerations, i.e. the 3 axes measured by the triaxial accelerometer.

Terrier et al.

Terrier et al. BMC Musculoskeletal Disorders 2013 14:94   doi:10.1186/1471-2474-14-94

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