Obesity, but not overweight, is associated with plantar light touch sensation in children aged 8 to 16 years: A cross‐sectional study

Abstract

Summary Objective Increased foot‐ground contact loading engenders adaptive glabrous skin thickening and can decrease mechanoreceptor acuity and alter plantar cutaneous sensation. There has not been any research on whether overweight and obesity are similarly associated with normal plantar cutaneous sensation scores in children. This study investigated the associations between normal plantar cutaneous sensation scores and weight status (i.e., healthy weight, overweight, and obesity) in a sample of youth. Methods Plantar sensation was tested among 122 participants aged 8 to 16 years (10.3 ± 1.8 years; 140.0 ± 11.2 cm; 44.2 ± 16.0 kg) across the forefoot, midfoot, and rearfoot using Semmes‐Weinstein pressure aesthesiometry (0.07 g and 0.4 g monofilaments). Weight status was determined using the Centers for Disease Control and Prevention growth charts. Age‐ and sex‐adjusted models were used to explore the relationships between normal plantar sensation scores and weight status. Significant two‐tailed tests were set at p < .05. Results Only obesity was inversely associated with normal plantar sensation scores on the left (β = −.241; p = .009) and right (β = −.222; p = .018) forefeet, left (β = −.322; p = .001) and right (β = −.253; p = .007) midfeet, and left (β = −.286; p = .002) and right (β = −.228; p = .014) wholefeet (relative to healthy weight) when using the 0.07 g monofilament. There was no association between obesity and plantar sensation when using the 0.4 g monofilament. Conclusions Obesity is associated with diminished light touch plantar sensation. Considering previously reported higher mechanical loading and the fact that Merkel cells and the Aβfibers that innervate them are superficial to the hypodermis, adaptive glabrous skin thickening (rather than fat pad thickness) may underlie this association. Contrary to previous suggestions, overweight is not associated with decreased plantar cutaneous sensation.

Associations Between Women’s Obesity Status and Diminished Cutaneous Sensibility Across Foot Sole Regions

“…(2015) showed that skin hardness was positively correlated not only with perceptual threshold but also with afferent firing by fast adapting foot sole mechanoreceptors. These findings support the Ajisafe et al. (2020) hypothesis.…”

“…Our study revealed a detailed map of cutaneous foot sole sensibility decay in the participant group with morbid obesity that warrants further explanation. In an attempt to explain the low foot sole sensibility of individuals with obesity, Ajisafe et al. (2020) suggested that obesity and associated mechanical stress to support heavier body weight in daily living tasks lead to adaptive glabrous skin thickening.…”

“…In fact, increased foot sole pressure due to low-moderate obesity has been found to be associated with decreased foot sole sensibility (Ajisafe et al., 2020; da Rocha et al., 2014; Wu & Madigan, 2014; Yümin et al., 2016). Comparing children with obesity to their lean peers, da Rocha et al.…”

“…Additionally, these authors observed that children who were not overweight had varied cutaneous sensibility across different foot sole regions, while children who were overweight did not. Ajisafe et al. (2020) evaluated the different associations between body weight and cutaneous foot sole sensibility for youth with healthy weight, overweight, and obese status and found that obesity, but not overweight status, was inversely associated with foot sole sensibility.…”