title: Obstacle crossing in lower limb amputees.
abstract: OBJECTIVE
  To study limitations in function and adjustment strategies in lower limb amputees during obstacle crossing.
  
  
  METHODS
  Observational cohort study.
  
  
  METHODS
  Transfemoral and transtibial amputees and able-bodied control subjects.
  
  
  METHODS
  In a motion analysis laboratory unimpeded and obstacle crossing runs were performed. The subjects stepped over an obstacle of 0.1m height and thickness and 1m width. Outcome measures were gait velocity, hip, knee and ankle joint angles and leading limb preference.
  
  
  RESULTS
  Whereas able-bodied and transtibial subjects demonstrated an increase in knee flexion during obstacle crossing compared to unimpeded walking, in transfemoral amputees the opposite was seen, namely a decrease in knee flexion. The lack of knee strategy in transfemoral amputees was compensated by circumduction at the hip on the prosthetic side and plantar flexion of the non-affected ankle. Transtibial amputees preferred to cross the obstacle with the prosthetic limb first, while transfemoral amputees preferred the non-affected limb.
  
  
  CONCLUSIONS
  The different leading limb strategy in transfemoral and transtibial amputees could be explained by the restricted flexion and propulsion properties of the prosthetic knee. Training of obstacle crossing tasks during rehabilitation and improvement of prosthetic design may contribute to safe obstacle crossing.
authors.affiliation: Center for Rehabilitation, University Medical Center Groningen, University of Groningen, Hanzeplein 1, P.O. Box 30001, 9700 RB Groningen, The Netherlands. a.h.vrieling@rev.umcg.nl
authors.forename: A H
authors.initials: AH
authors.lastname: Vrieling
authors.forename: H G
authors.initials: HG
authors.lastname: van Keeken
authors.forename: T
authors.initials: T
authors.lastname: Schoppen
authors.forename: E
authors.initials: E
authors.lastname: Otten
authors.forename: J P K
authors.initials: JP
authors.lastname: Halbertsma
authors.forename: A L
authors.initials: AL
authors.lastname: Hof
authors.forename: K
authors.initials: K
authors.lastname: Postema
mesh_terms: D000222:Adaptation, Physiological; D000674:Amputees; D000704:Analysis of Variance; D000843:Ankle Joint / Q000502:physiology; D001186:Artificial Limbs; D001696:Biomechanical Phenomena; D005260:Female; D005684:Gait / Q000502:physiology*; D006621:Hip Joint / Q000502:physiology; D006801:Humans; D007719:Knee Joint / Q000502:physiology; D008297:Male; D008875:Middle Aged; D004856:Postural Balance / Q000502:physiology; D016059:Range of Motion, Articular; D014743:Videotape Recording; D016138:Walking / Q000502:physiology*