title: The contribution of type of daily activity to loading across the hip and knee joints in the elderly.
abstract: OBJECTIVE
  In the elderly, we evaluated loading across the hip or knee joints during different daily activities.
  
  
  METHODS
  Elderly people drawn from the community entering an exercise study underwent a full kinetic and kinematics analysis of five different activities, standing, walking, arising from a chair, going downstairs and bending over. Inverse dynamic equations were used to compute forces and torques across the knees and hips during all of these activities.
  
  
  RESULTS
  132 elderly people, mean age 75, participated. Compressive forces across the knees and hips were, by far, the greatest vector forces and were highest during stair descent and, to a lesser extent, during walking. Compressive forces were lowest during standing. The highest moments were flexion and adduction moments, and these were maximal during stair descent.
  
  
  CONCLUSIONS
  Of the five activities we studied, descending stairs was associated with the highest calculated forces and torques across the knees and hips, and that may account for its tendency to cause joint symptoms and for its possible association with osteoarthritis incidence.
authors.affiliation: Massachusetts General Hospital Biomotion Laboratory, Boston Medical Center, MA, USA.
authors.forename: N
authors.initials: N
authors.lastname: Luepongsak
authors.forename: S
authors.initials: S
authors.lastname: Amin
authors.forename: D E
authors.initials: DE
authors.lastname: Krebs
authors.forename: C A
authors.initials: CA
authors.lastname: McGibbon
authors.forename: D
authors.initials: D
authors.lastname: Felson
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D005260:Female; D006621:Hip Joint / Q000502:physiology*; D006801:Humans; D007719:Knee Joint / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D010003:Osteoarthritis / Q000209:etiology*; D005082:Physical Exertion / Q000502:physiology*; D012307:Risk Factors; D013314:Stress, Mechanical; D016474:Weight-Bearing