## 3 Results  
Among the 13 patients, seven patients had symptomatic heel spurs on two feet. Since the longest spur was used in this study, a total of 20 feet were evaluated. The length of spur (L) ranged between 1.5 and 7 mm, as presented in detail in Table 1. According to Table 1, three classifications are determined: (1) there are two patients with small length of spur, with average L of 1.75 \(\pm\) 0.35 mm; (2) there are seven patients with medium length of spur, with average L of 3.93 \(\pm\) 0.73 mm; and (3) there are four patients with large length of spur, with average L of 6.50 \(\pm\) 0.58 mm. Based on data of FL and FW, we can obtain the shoe size of each patient [33]; one patient has shoe size 37; four patients have shoe size 38; one patient has shoe size 39; four patients have shoe size 40; two patients have shoe size 42; and one patient has shoe size 43. Thus, we summarize a total of six shoe sizes of 37-40 and 42-43. Each size is not made in the shoe form, but in the form of a foam impression (Figure 2c), and for variation in the shoe insole area of 0% A to 100% A, a total of 30 foam impressions were made. The distance measurements of the center of the heel (used for pressure measurement of sensor 2, Figure 1 up) and the base of the spur (used for PPT measurement of point 1, Figure 1 down) are not coincident. The distance from the center of the heel (CH) ranged between 35.1-41.4 mm, and the distance from the base of spur (S) ranged between 30-41 mm, where there were seven patients with the base of spur location on the right CH and six other patients at the left CH (the farthest distance of S and CH is 7 mm, and the closest is 0.4 mm). Figure 4: Illustration of the Force Sensing Resistor (FSR) sensor locations. The information on the results of PMCP measurements at each heel site is very important to know which sites have the smallest PMCP value. Table 2 shows the pressure pain sensitivity in patients with plantar heel pain due to a calcaneal spur at each heel site, where the PMCP ranged between 1.24-3.3 kg/cm\({}^{2}\) and averaged 2.09 \(\pm\) 0.63 kg/cm\({}^{2}\). The result shows that the smallest PMCP occurs at the anterior site, and the PMCP at the medial site was significantly lower than at the lateral site. The procedure to obtain n% insole foot area (Figure 3) produces the values of percentage deductions that can be applied to all of the shoe insoles (Table 3). The contour results of the foot of the shoe inside area of 0% A to 100% A from one of the study subjects are shown in Figure 5.  
According to the body weight (BW), there was a relationship between BW and the pressure in the calcaneal region. As the BW increases, the pressure at MH, LH and CH will increase as well [6]. There was a significant increase in pressure for the MH area, except at 100% A, with an average correlation coefficient of 0.74. At LH, a significant increase in pressure is seen at 0-50% A with an average correlation coefficient of 0.85. Furthermore, at CH, a significant increase in pressure is seen at 0-25% A with an average correlation coefficient of 0.85. To find the effect of area of shoe inside on the pressure of each pressure sensor in detail, it is easier to use a comparison of the pressure of each sensor to the BW or the total pressure of all sensors. Table 4 shows the distribution of pressure on the calcaneal region of one foot (assumed to be the same between left and right feet), expressed as