Abstract
Prosthetic alignment is an important factor in the overall fit and performance of a lower-limb prosthesis. However, the association between prosthetic alignment and control strategies used by persons with transfemoral amputation to coordinate the movement of a passive prosthetic knee is poorly understood. This study investigated the biomechanical response of persons with transfemoral amputation to systematic perturbations in knee joint alignment during a level walking task. Quantitative gait data were collected for three alignment conditions: bench alignment, 2 cm anterior knee translation (ANT), and 2 cm posterior knee translation (POST). In response to a destabilizing alignment perturbation (i.e., the ANT condition), participants significantly increased their early-stance hip extension moment, confirming that persons with transfemoral amputation rely on a hip extensor strategy to maintain knee joint stability. However, participants also decreased the rate at which they loaded their prosthesis, decreased their affected-side step length, increased their trunk flexion, and maintained their prosthesis in a more vertical posture at the time of opposite toe off. Collectively, these results suggest that persons with transfemoral amputation rely on a combination of strategies to coordinate stance-phase knee flexion. Further, comparatively few significant changes were observed in response to the POST condition, suggesting that a bias toward posterior alignment may have fewer implications in terms of stance-phase, knee joint control.
Original language | English (US) |
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Pages (from-to) | 1089-1106 |
Number of pages | 18 |
Journal | Journal of Rehabilitation Research and Development |
Volume | 53 |
Issue number | 6 |
DOIs | |
State | Published - 2016 |
Funding
This material was based on work supported by the VA, Office of Research and Development, Rehabilitation Research and Development Service (award VA RR&D RX000143) and was administered by the Jesse Brown VA Medical Center, Chicago, Illinois. This research was also partially funded by the Orthotics and Prosthetics Education and Research Foundation (grant OPERF-2009-FA-12) and the National Institute on Disability and Rehabilitation Research (NIDRR) of the U.S. Department of Education (grant H133E080009; Principal Investigators: Steven Gard and Stefania Fatone).
Keywords
- Alignment
- Amputation
- Artificial limbs
- Gait analysis
- Hip
- Knee
- Load cell
- Transfemoral
- Treadmill
- Trunk
ASJC Scopus subject areas
- Rehabilitation