Determining Asymmetry of Roll-Over Shapes in Prosthetic WalkingBy Curtze, Carolin; Otten, Bert; Hof, At L.; Postema, Klaas; Journal of Rehabilitation Research and Development, Volume 48, Number 10
Publication Date: 2011
Study determined the effect of the inherent asymmetry of the locomotor system in people with lower limb amputation on the ankle-foot rollover shape of prosthetic walking. Participants were 6 men with lower limb amputation aged 37 to 66 years, of whom 3 were transtibial and 3 were transfemoral, and 3 matched controls without disabilities. While participants walked at self-selected speed, ground reaction forces during a complete stride cycle were measured using two force plates sampling at a rate of 100 hertz. An 8 camera motion capture system tracked reflection markers placed on participants’ limbs and prostheses. Participants’ walking patterns were analyzed in terms of rollover characteristics and spatial and temporal factors. The level of asymmetry was determined by rollover shape comparison as well as differences in radius of curvature. In addition, ratios were calculated to determine spatial and temporal asymmetries, and different aspects of asymmetry of rollover shapes were determined. All participants showed some level of asymmetry in rollover shape, even the controls. Furthermore, good intralimb reproducibility was found for the group as a whole. With respect to spatial and temporal factors, the participants with transtibial amputation had a quite symmetrical gait pattern, while the gait pattern in the participants with transfemoral amputation was more asymmetrical. The individual ankle-foot rollover shapes provided additional insight into the marked individual adjustments occurring during the stance phase of the nondisabled limb. The authors conclude that the two methods presented are suitable for determining asymmetry of rollover shapes, and both methods should be used complementarily. Study limitations and implications for future research are discussed.
VA Rehabilitation Research & Development Service (Web Site: http://www.rehab.research.va.gov )
Link to text: http://www.rehab.research.va.gov/jour/11/4810/curtze4810.html