There were no differences between the groups regarding age, height, body mass, and body mass index (BMI) (Table 1). The results of the neuropathic and vascular assessments are shown in Table 2. There was no difference in foot contact time (stance phase duration) during the pressure measurements between C, DC and DN (data not shown). Footprint characteristics were not different between the groups and the mean (SD) arch index for the whole study population was 0.23 (0.05) (Table 3). This mean value indicates the presence of a normal arch type across all subjects analyzed.
No significant associations were observed between arch index and peak pressure of the foot (r = 0.078) and maximum pressure time integral (PTI) of the foot (r = -0.007). The association between arch index and peak pressure under the first MTH did not reach statistical significance (r = 0.34, p=0.051), as did the association between the arch index and the PTI under the first MTH (r = 0.29, p = 0.095).
There were no significant differences in peak pressure or PTI at any regional site between groups with different arch height, although a non-significant trend was observed towards higher medial peak pressures in the low arch group (Figure 2). The median peak pressure (inter-quartile range) at the first MTH was 566 kPa (366-764) in the low arch group, while this was 296 kPa (243-403) in the high arch group. In addition, non-significant trends were observed towards a greater PTI at the medial side of the forefoot in the low arch group compared to the high arch group (Figure 3).
Peak pressure versus arch-height. Median peak pressures for the whole study population (n=34) for the whole foot and each individual site for subjects with a high, normal and low arch. There were no significant differences in peak pressure between the three groups at any of the regions.
Peak pressure time integral versus arch-height. Median peak pressure time integral (PTI) for the whole study population (n=34) for the whole foot and each individual site for subjects with a high, normal and low arch. There were no significant differences in PTI between the three groups at any of the regions.
A higher (mean ± SD) BMI was observed in the low arch group compared to the high arch group (28.6 ± 4.8 vs 24.3 ± 3.3 kg/m2, p<0.05). In addition, there was a significant association between BMI and arch index (r = 0.36, p<0.05), but not between weight and arch index (r = 0.25, p=0.16). This indicates that a higher body mass (i.e., BMI) lowers the arch of the foot, although no significant difference in body mass between the three groups was detected.
Body mass was significantly associated with peak pressure of the foot (r = 0.38; p<0.05), and with peak pressure at the fourth, second, and first MTH (r = 0.38, 0.39 and 0.41; p<0.05). The association between body mass and maximum PTI of the foot did not reach statistical significance (r = 0.33; p = 0.056), but was significant for PTI at the fourth, third, second and first MTH (r = 0.39, 0.35, 0.47 and 0.36; p<0.05).
Wounds. 2000;12(4) © 2000 Health Management Publications, Inc.
Copyright © 1999 by HMP Communications, LLC All rights reserved.
Cite this: The Effect of Arch Height and Body Mass on Plantar Pressure - Medscape - Sep 01, 2000.