title: Characteristics of foot morphology and their relationship to gender, age, body mass index and bilateral asymmetry in Japanese adults.
abstract: BACKGROUND
  Different characteristics of foot morphology are commonly accompanied by altering lower extremity biomechanical characteristics and foot function. Clarifying what factors affect foot morphology is helpful in understanding the basis of foot deformity and foot dysfunction.
  
  
  OBJECTIVE
  The aim of this study was to investigate characteristics of foot morphology and whether related factors such as gender, age, body mass index (BMI) and bilateral asymmetry have an impact on foot morphology.
  
  
  METHODS
  One hundred and eighty adults without exercise habit were included in this cross-sectional study. Participants were categorized by gender, age, BMI, and left and right foot respectively to compare foot morphology differences. The characteristics of foot morphology were measured using a 3D foot scanner.
  
  
  RESULTS
  Compared with females, males had longer, larger and higher feet. In terms of age differences, older adults had shorter and stiffer feet. Regarding BMI differences, the value of height and width parameters of foot was larger, and the value of height of arch also larger in those with greater BMI. Regarding bilateral asymmetry, the right foot had a higher foot than the left foot. Multiple linear regression models indicated that gender, age and BMI significantly affected length and girth parameters of foot together.
  
  
  CONCLUSIONS
  This study showed that gender has a bigger impact on length, width, height and girth parameters of foot than BMI or age. BMI has an impact on both arch height and stiffness. Besides, bilateral asymmetry affects values of height parameters of foot and arch.
authors.affiliation: Doctoral Program in Sports Medicine, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki, Japan.
authors.forename: Xiaoguang
authors.initials: X
authors.lastname: Zhao
authors.affiliation: Faculty of Health and Sports Sciences, University of Tsukuba, Ibaraki, Japan.
authors.forename: Takehiko
authors.initials: T
authors.lastname: Tsujimoto
authors.affiliation: Doctoral Program in Sports Medicine, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki, Japan.
authors.forename: Bokun
authors.initials: B
authors.lastname: Kim
authors.affiliation: Faculty of Education, Kogakkan University, Mie, Japan.
authors.forename: Yasutomi
authors.initials: Y
authors.lastname: Katayama
authors.affiliation: Faculty of Health and Sports Sciences, University of Tsukuba, Ibaraki, Japan.
authors.forename: Kiyoji
authors.initials: K
authors.lastname: Tanaka
mesh_terms: D000328:Adult; D000375:Aging / Q000473:pathology*; D044466:Asian People; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D015444:Exercise; D005260:Female; D005528:Foot / Q000033:anatomy & histology*; D005530:Foot Deformities; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D012727:Sex Characteristics
keywords: Foot length; foot arch; foot deformities; foot girth; foot width