title: Age-related differences in inter-joint coordination during stair walking transitions.
abstract: Stair negotiation is one of the most difficult and hazardous locomotor tasks for older adults with fall-related accidences reported frequently. Since knowledge about inter-joint coordination during stair walking provides insights to age-related changes in neuromuscular control of gait that can inform prevention or intervention strategies, the current study investigated the effect of age on the pattern and variability of inter-joint coordination during stair-floor transitions during gait. Gait and motion analyses of the lower extremities of 20 young and 20 older adults during floor to stair (F-S) and stair to floor (S-F) walking transitions provided continuous measures of relative phase (CRP) that assessed inter-joint coordination of the hip, knee, and angle joints. The mean absolute relative phase (MARP) and deviation phase (DP) provided descriptive metrics for CRP pattern and variability respectively. For hip-knee CRP pattern, older adults demonstrated significantly smaller MARP than young adults in stance and most swing phases during F-S and S-F. For knee-ankle, older adults showed a significant smaller MARP of the trailing limb during S-F than young adults. In most stance and swing phases, the hip-knee DP values of older adults were significantly lower than that of young adults. Significant lower knee-ankle DP values of older adults were only detected in swing phase during S-F. The findings suggest that normal aging adults have less independent control of adjacent joints compared to younger adults suggesting they have less flexibility to modulate inter-joints coordination appropriately during stair walking transitions.
authors.affiliation: Department of Environmental Health, Harvard School of Public Health, Boston, MA, USA; Liberty Mutual Research Institute for Safety, Hopkinton, MA, USA.
authors.forename: Shiu-Ling
authors.initials: SL
authors.lastname: Chiu
authors.affiliation: Department of Industrial Engineering & Engineering Management, National Tsing Hua University, Taiwan, ROC. Electronic address: max.chang@ie.nthu.edu.tw.
authors.forename: Chien-Chi
authors.initials: CC
authors.lastname: Chang
authors.affiliation: Department of Environmental Health, Harvard School of Public Health, Boston, MA, USA; Department of Physical Therapy, Movement, and Rehabilitation Sciences, Bouvé College of Health Sciences, Northeastern University, Boston, MA, USA.
authors.forename: Jack T
authors.initials: JT
authors.lastname: Dennerlein
authors.affiliation: Liberty Mutual Research Institute for Safety, Hopkinton, MA, USA.
authors.forename: Xu
authors.initials: X
authors.lastname: Xu
mesh_terms: D000054:Acceleration; D000058:Accidental Falls; D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D005260:Female; D005684:Gait / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011597:Psychomotor Performance; D012016:Reference Values; D016138:Walking / Q000502:physiology*; D055815:Young Adult
keywords: Aging; Coordination; Gait; Stair negotiation; Variability