Goeran Fiedler

Introduction Advances in the rehabilitation of persons with limb loss are often attributed to the development of sophisticated prosthetic technology. While, as an engineer, I admire the technological breakthroughs that have been achieved over recent years, I recognize that successful rehabilitation requires more. In my 12 years of experience as a prosthetist & orthotist I often found that expensive, high-end componentry had a relatively small impact on the majority of my patients that used artificial limbs. Instead I noted that factors such as socket fit and static alignment determined the functional outcome of my patients, regardless of the componentry they were wearing. In my view, optimizing these factors is a more economically efficient and universally applicable way of improving prosthesis performance than is providing advanced componentry. I have found that many of my clinical and scientific colleagues share this view. Scientific evidence to support this perspective, however, remains still scarce. My research goals are therefore to investigate methods for the objective evaluation of prosthesis fit and alignment. Specific research interests include assessment with respect to activity, participation, and long-term prognoses. Finally, I am interested in adapting methods and findings from this research to studies that involve other populations with similar functional deficits. Graduate Research For my dissertation research, I investigated the influence of alignment and fatigue on prosthetic gait. This work was motivated by the finding that assessment of prosthetic fit and alignment may often not be entirely accurate, reliable or efficient. Instrumented gait analysis, the gold standard for assessing human movement, is rarely applicable in the clinical field where the required time, space, and equipment are often not available. Furthermore, the controlled conditions of a gait laboratory likely differ from those in a prosthesis user's daily life. In my study, I focused on quantifying those differences, and evaluating the potential of mobile gait assessment methods. Postdoctoral Research During the duration of my post-doctoral training, I have been collaborating with my mentors to evaluate previously processed and unprocessed data from my dissertation study, in an effort to better define future research directions and to identify additional research hypotheses. I also joined an active research project in the Department of Bioengineering at the University of Washington. The purpose of this project is to investigate the effects of various modes of feedback information on gait biomechanics in persons with lower limb prostheses to improve the efficiency and safety of rehabilitation regimens in populations with limb loss. Ongoing and Planned Research During my time here at the University of Pittsburgh, I have been working on two new studies. One is investigating the hypothesis that prosthesis users walk differently when they are under observation than in situations where nobody is analyzing their gait. There is some evidence, that this is the case for able-bodied people, and it would have interesting implications on the validity of the common practice of aligning prostheses merely in the fitting room or gait lab. The purpose of the second study is to possibly find a correlation between alignment quality and step variability in lower limb prosthesis users. This would provide a (fairly easily) measurable outcome criterion for alignment quality. Alignment optimization is particularly interesting to me, as it requires comparably modest investments in equipment and resources yet findings can be applied to a large population including persons with different amputation levels, activity classifications, or prosthesis designs. This eases the translation of scientific findings into clinical practice. I believe that research in this area has potential for significant changes in prosthesis alignment optimization and outcome assessment.