Table 3 Impact of foot and ankle morphology on the stiffness of each structure in neutral position and then in functional position

Spring ligament

 Normal

4.56 ± 0.57

4.29 ± 0.95

4.93 ± 0.63

0.19

4.42 ± 0.65

4.49 ± 0.75

4.61 ± 0.93

0.96

 Valgus 20°

5.5 ± 0.69

5.68 ± 1.09

6.64 ± 1.09

0.01

5.64 ± 1.01

6.49 ± 1.1

5.74 ± 1.07

0.13

 Varus 30°

4.34 ± 0.82

4.76 ± 1.32

5.05 ± 0.89

0.22

4.75 ± 0.76

5.28 ± 1.34

4.5 ± 0.93

0.19

Posterior tibialis tendon (PTT)

 Normal

6.61 ± 0.61

6.3 ± 0.86

6.42 ± 0.69

0.41

6.62 ± 1.02

6.47 ± 0.78

6.28 ± 0.66

0.58

 Valgus 20°

7.47 ± 0.96

7.66 ± 0.95

7.57 ± 0.92

0.71

7.52 ± 0.88

7.91 ± 0.96

7.47 ± 0.92

0.47

 Varus 30°

6.53 ± 0.92

6.23 ± 0.8

5.91 ± 0.65

0.14

6.51 ± 1.06

6.24 ± 0.92

6.08 ± 0.61

0.57