*Sensors* **2019**, *19*, 1328

Static mobility grades of IMTT (sensor 1) and PPH (sensor 2) bones in unshod and 3 cm, 6 cm and 9 cm heel height are summarized in Table 4. The dynamic mobility grades of both sensor 1 and sensor 2 in unshod and 3 cm, 6 cm and 9 cm heel heights in Table 5.

Under static conditions, the PPH abduction increases from 1.01 ± 0.36◦ to 1.31 ± 0.46◦ (*p* < 0.05) after wearing shoes with a 3 cm heel. There was a statistically significant valgus of the I MTT with increasing heel heights from 1.77 ± 0.20◦ without high heels to 2.15 ± 0.10◦ with 3 cm (*p* < 0.001) high heels. There was increased varus movement from 1.50 ± 0.23 to 3.87 ± 0.20 with 3 cm heels (*p* < 0.001).

In dynamic tests, wearing shoes with 6 cm high heels led to an increase in PPH valgus and abduction deviation from 3.15 ± 0.10◦ to 3.46 ± 0.05◦ (*p* < 0.05) and from 1.35 ± 0.28◦ to 1.69 ± 0.30◦ (*p* < 0.001), respectively. In addition, PPH had abduction that increased to 1.91 ± with 9 cm heels (*p* < 0.001). On the other hand, I MTT had a valgus decrease with 6 cm heels (from 3.94 ± 0.28 to 3.70 ± 0.13 (*p* < 0.001)) but without any concordance correlation.


**Table 4.** STATIC mobility grades of first metatarsal (sensor 1) and proximal phalanx of hallux (sensor 2) bones in unshod with heels of 3 cm, 6 cm, and 9 cm high.

Abbreviations: MTT ADD = first metatarsal bone in Adduction: I MTT toward to medial body line; MTT ABD = first metatarsal bone in abduction: I MTT away to medial body line; MTT PF = first metatarsal bone in plantarflexion: I MTT toward to the floor; MTT DF = first metatarsal bone in dorsiflexion: I MTT away to the floor; MTT VL = first metatarsal bone spins to inside: I MTT toward medial body line; MTT VR = first metatarsal bone spin to outside: I MTT away to medial body line; UNSHOD = barefoot participants without any height in shoe heel; PPH ADD = proximal phalanx of hallux in adduction: PPH toward to medial body line; PPH ABD = proximal phalanx of hallux in Abduction: PPH away to medial body line; PPH PF = proximal phalanx of hallux in plantarflexion: PPH toward to the floor; PPH DF = proximal phalanx of hallux in dorsiflexion: PPH away to the floor; PPH VL = proximal phalanx of hallux spins to inside: PPH toward medial body line; PPH VR = proximal phalanx of hallux spin to outside: PPH away to medial body line; ±SD = standard deviation; *p-*value < 0.05 **\*** (within a 95% confidence interval) was considered statistically significant; *p-*value < 0.001 \*\* (within a 95% confidence interval) was considered statistically strong significant; Movements and axes refer to the medial line of the body; all values are expressed in degrees.


**Table 5.** DYNAMIC mobility grades of first metatarsal (sensor 1) and proximal phalanx of hallux (sensor 2) bones in unshod as well as heels 3 cm, 6 cm and 9 cm high.

Abbreviations: MTT ADD = first metatarsal bone in Adduction: I MTT toward to medial body line; MTT ABD = first metatarsal bone in Abduction: I MTT away to medial body line; MTT PF = first metatarsal bone in plantarflexión: I MTT toward to the floor; MTT DF = first metatarsal bone in dorsiflexión: I MTT away to the floor; MTT VL = first metatarsal bone spins to inside: I MTT toward medial body line; MTT VR = first metatarsal bone spin to outside: I MTT away to medial body line; UNSHOD = barefoot participants without any height in shoe heel; PPH ADD = proximal phalanx of hallux in Adduction: PPH toward to medial body line; PPH ABD = proximal phalanx of hallux in Abduction: PPH away to medial body line; PPH PF = proximal phalanx of hallux in plantarflexión: PPH toward to the floor; PPH DF = proximal phalanx of hallux in dorsiflexión: PPH away to the floor; PPH VL = proximal phalanx of hallux spins to inside: PPH toward medial body line; PPH VR = proximal phalanx of hallux spin to outside: PPH away to medial body line; ±SD = standard deviation; *p-*value < 0.05 \* (within a 95% confidence interval) was considered statistically significant; *p-*value < 0.001 \*\* (within a 95% confidence interval) was considered statistically strong significant; Movements and axes refer to the medial line of the body; all values are expressed in degrees.

Finally, Tables 6 and 7 summarize the Spearman's Rho correlation coefficients of static and dynamic conditions between the height of the heels and the movements of PPH and I MTT, respectively.

In static tests, adduction of IMTT had a statistically significant positive correlation while wearing 6 cm heels versus unshod condition (0.5, *p* < 0.001) as well as abduction (0.347, *p* < 0.001). Valgus values had a statistically significant positive correlation too under 3 cm high heel (0.51, *p* < 0.001). Regarding PPH abduction, there was a statistical positive correlation in 6 cm heels (0.261, *p* < 0.05) as well as a statistically significant negative correlation to adduction under 3 cm and 6 cm of high heels (*p* < 0.05).

During dynamic tests, PPH abduction had a statistically significant positive correlation with heels of 6 cm (0.527, *p* < 0.001) combined with a statistically significant inverse correlation in adduction (−0.278, *p* < 0.05) with 6 cm; there was a significant positive correlation with valgus values (0.242, *p* < 0.05).


Abbreviations: ρ-coefficient = Spearman Rho coefficient; MTT ADD = first metatarsal bone in adduction: I MTT toward to medial body line; MTT ABD = first metatarsal bone in abduction: I MTT away to medial body line; MTT PF = first metatarsal bone in plantarflexion: I MTT toward to the floor; MTT DF = first metatarsal bone in dorsiflexion: I MTT away to the floor; MTT VL = first metatarsal bone spins to inside: I MTT toward medial body line; MTT VR = first metatarsal bone spin to outside: I MTT away to medial body line; UNSHOD = barefoot participants without any height in shoe heel; PPH ADD = proximal phalanx of hallux in adduction: PPH toward to medial body line; PPH ABD = proximal phalanx of hallux in abduction: PPH away to medial body line; PPH PF = proximal phalanx of hallux in plantarflexion: PPH toward to the floor; PPH DF = proximal phalanx of hallux in dorsiflexion: PPH away to the floor; PPH VL = proximal phalanx of hallux spins to inside: PPH toward medial body line; PPH VR = proximal phalanx of hallux spin to outside: PPH away to medial body line; ±SD = standard deviation; *p*-value < 0.05 \* (within a 95% confidence interval) was considered statistically significant; *p*-value < 0.001 \*\* (within a 95% confidence interval) was considered statistically strong significant; Movements and axes refer to the medial line of the body; all values are expressed in degrees.



Abbreviations: ρ-coefficient = Spearman Rho coefficient; MTT ADD = first metatarsal bone in Adduction: I MTT toward to medial body line; MTT ABD = first metatarsal bone in abduction: I MTT away to medial body line; MTT PF = first metatarsal bone in plantarflexion: I MTT toward to the floor; MTT DF = first metatarsal bone in dorsiflexion: I MTT away to the floor; MTT VL = first metatarsal bone spins to inside: I MTT toward medial body line; MTT VR = first metatarsal bone spin to outside: I MTT away to medial body line; UNSHOD = barefoot participants without any height in shoe heel; PPH ADD = proximal phalanx of hallux in adduction: PPH toward to medial body line; PPH ABD = proximal phalanx of hallux in abduction: PPH away to medial body line; PPH PF = proximal phalanx of hallux in plantarflexion: PPH toward to the floor; PPH DF = proximal phalanx of hallux in dorsiflexion: PPH away to the floor; PPH VL = proximal phalanx of hallux spins to inside: PPH toward medial body line; PPH VR = proximal phalanx of hallux spin to outside: PPH away to medial body line; ±SD = standard deviation; *p*-value < 0.05 \* (within a 95% confidence interval) was considered statistically significant; *p*-value < 0.001 \*\* (within a 95% confidence interval) was considered statistically strong significant; Movements and axes refer to the medial line of the body; all values are expressed in degrees.
