title: Differences in knee flexion between the Genium and C-Leg microprocessor knees while walking on level ground and ramps.
abstract: BACKGROUND
  Microprocessor knees have improved the gait and functional abilities of persons with transfemoral amputation. The Genium prosthetic knee offers an advanced sensor and control system designed to decrease impairment by: allowing greater stance phase flexion, easing transitions between gait phases, and compensating for changes in terrain. The aim of this study was to determine differences between the knee flexion angle of persons using the Genium knee, the C-Leg knee, and non-amputee controls; and to evaluate the impact the prostheses on gait and level of impairment of the user.
  
  
  METHODS
  This study used a randomized experimental crossover of persons with transfemoral amputation using the Genium and C-Leg microprocessor knees (n=25), with an observational sample of non-amputee controls (n=5). Gait analysis by 3D motion tracking of subjects ambulating at different speeds on level ground and on 5° and 10° ramps was completed.
  
  
  RESULTS
  Use of the Genium resulted in a significant increase in peak knee flexion for swing (5°, p<0.01, d=0.34) and stance (2°, p<0.01, d=0.19) phases relative to C-Leg use. There was a high degree of variability between subjects, and significant differences still remain between the Genium group and the control group's knee flexion angles for most speeds and slopes.
  
  
  CONCLUSIONS
  The Genium knee generally increases flexion in swing and stance, potentially decreasing the level of impairment for persons with transfemoral amputation. This study demonstrates functional differences between the C-Leg and Genium knees to help prosthetists determine if the Genium will provide functional benefits to individual patients.
authors.affiliation: Florida Gulf Coast University, Department of Bioengineering and Software Engineering, Fort Myers, FL, USA, 33965. Electronic address: dlura@fgcu.edu.
authors.forename: Derek J
authors.initials: DJ
authors.lastname: Lura
authors.affiliation: University of South Florida, Mechanical Engineering Department, Tampa, FL, USA, 33620.
authors.forename: Matthew M
authors.initials: MM
authors.lastname: Wernke
authors.affiliation: University of South Florida, Mechanical Engineering Department, Tampa, FL, USA, 33620.
authors.forename: Stephanie L
authors.initials: SL
authors.lastname: Carey
authors.affiliation: University of South Florida, School of Physical Therapy and Rehabilitation Sciences, Tampa, FL, USA, 33620.
authors.forename: Jason T
authors.initials: JT
authors.lastname: Kahle
authors.affiliation: University of South Florida, School of Physical Therapy and Rehabilitation Sciences, Tampa, FL, USA, 33620; University of South Florida, Center for Neuromusculoskeletal Research, Tampa, FL, USA, 33620.
authors.forename: Rebecca M
authors.initials: RM
authors.lastname: Miro
authors.affiliation: University of South Florida, School of Physical Therapy and Rehabilitation Sciences, Tampa, FL, USA, 33620; University of South Florida, Center for Neuromusculoskeletal Research, Tampa, FL, USA, 33620.
authors.forename: M Jason
authors.initials: MJ
authors.lastname: Highsmith
mesh_terms: D000671:Amputation, Surgical / Q000534:rehabilitation; D001696:Biomechanical Phenomena; D018592:Cross-Over Studies; D005260:Female; D005684:Gait / Q000502:physiology*; D006801:Humans; D007717:Knee / Q000502:physiology*; D007720:Knee Prosthesis; D007866:Leg / Q000502:physiology; D008297:Male; D008838:Microcomputers; D008875:Middle Aged; D011474:Prosthesis Design; D016059:Range of Motion, Articular; D016138:Walking / Q000502:physiology*
keywords: C-Leg; Genium; Knee flexion; Lower limb; Microprocessor knees (MPK); Prosthetics; Transfemoral amputee (TFA)