headshot of Goeran Fiedler

Goeran Fiedler

Associate Professor
Assistant Professor
gfiedler@pitt.edu
(412) 624-6475
(412) 624-8063
Bioengineering Department

overview

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.

about

(2014) Best Mentor Award, Research Experience for Undergrads program.

(2012) Force and Motion Foundation, Travel Grant.

(2011) UWM College of Health Sciences Student Research Grant.

(2011) UWM Chancellor's Award.

(2006) Fulbright Travel Grant.

B of Crafts, Prosthetics & Orthotics, Chamber of Crafts Thuringia, 1990 - 1994

M of Crafts, Prosthetics & Orthotics, Chamber of Crafts Lower Bavaria/Upper Palatinate, 1998 - 1998

n/a, Physics, University Georgia Augusta, 2002 - 2004

Dipl. Ing., Clinical Engineering/Biomechanics, University of Applied Sciences, 2004 - 2008

PhD, Health Sciences, University of Wisconsin - Milwaukee, 2008 - 2012

Anderst, W., Fiedler, G., Onishi, K., McKernan, G., Gale, T., & Paulus, P. (2022). Within-subject effects of standardized prosthetic socket modifications on physical function and patient-reported outcomes. Trials, 23(1), 299.Springer Nature. doi: 10.1186/s13063-022-06205-z.

Fiedler, G., Singh, A., & Zhang, X. (2020). Effect of temperature-control liner materials on long-term outcomes of lower limb prosthesis use: a randomized controlled trial protocol. Trials, 21(1), 61.Springer Nature. doi: 10.1186/s13063-019-3920-4.

Fiedler, G., & Kremer, U. (2017). Self-efficacy in Prosthetics & Orthotics students who did and did not participate in short term study abroad programs - preliminary results. Z Evid Fortbild Qual Gesundhwes, 121, 36-41.Elsevier. doi: 10.1016/j.zefq.2016.11.006.

Fiedler, G., & Zhang, X. (2016). Quantifying accommodation to prosthesis interventions in persons with lower limb loss. Gait Posture, 50, 14-16.Elsevier. doi: 10.1016/j.gaitpost.2016.08.016.

Fiedler, G., Slavens, B.A., O'Connor, K.M., Smith, R.O., & Hafner, B.J. (2016). Effects of physical exertion on trans-tibial prosthesis users' ability to accommodate alignment perturbations. Prosthet Orthot Int, 40(1), 75-82.Wolters Kluwer. doi: 10.1177/0309364614545419.

Malchow, C., & Fiedler, G. (2016). Effect of observation on lower limb prosthesis gait biomechanics: Preliminary results. Prosthet Orthot Int, 40(6), 739-743.Wolters Kluwer. doi: 10.1177/0309364615605374.

Fiedler, G. (2015). Vergleich der Versorgungsergebnisse mit verschiedenen trans-femoralen Schaftkonzepten [Outcome comparison of different trans-femoral socket designs]. Orthopädie-Technik, 66(4), 42-45.

Fiedler, G. (2014). Möglichkeiten und Limitationen des Einsatzes von prothesen-integrierter Ganganalysetechnologie in der transtibialen Prothetik, Eine Zusammenfassung erster Studienergebnisse. [Prospects & limitations of prosthesis-integrated gait analysis technology]. Orthopädie-Technik, 65(12), 18-23.

Fiedler, G., Akins, J., Cooper, R., Munoz, S., & Cooper, R.A. (2014). Rehabilitation of People with Lower-Limb Amputations. Current Physical Medicine and Rehabilitation Reports, 2, 1-10.

Fiedler, G., Slavens, B., Smith, R.O., Briggs, D., & Hafner, B.J. (2014). Criterion and construct validity of prosthesis-integrated measurement of joint moment data in persons with transtibial amputation. J Appl Biomech, 30(3), 431-438.Human Kinetics. doi: 10.1123/jab.2013-0309.

Fiedler, G. (2013). Mobile Kinetik-Sensoren in der Orthopädietechnik, Evaluierung von Amputationsversorgungen der unteren Extremität mit prothesenintegrierter Ganganalyse. [Mobile kinetics sensors in Prosthetics & Orthotics, Assessment of lower limb prostheses by means. MT-Medizintechnik, 13(3), 102-106.

Fiedler, G., Slavens, B.A., Hafner, B.J., Briggs, D., & Smith, R.O. (2013). Leg Laterality Differences in Persons with Bilateral Transtibial Amputation. JPO Journal of Prosthetics and Orthotics, 25(4), 168-176.Wolters Kluwer. doi: 10.1097/jpo.0000000000000005.

Guenther, M., & Fiedler, G. (2011). Der Milwaukee-Schaft - wissenschaftliche Ergebnisse als Grundlage für ein verbessertes transfemorales Schaftdesgin. [The Milwaukee Socket - an improved trans-femoral socket design based on scientific findings]. Orthopädie-Technik, 11(2), 93-95.

Papaioannou, G., Tsiokos, D., Fiedler, G., Mitrogiannis, C., Avdeev, I., Wood, J., & McKinney, R. (2011). Dynamic Radiography Imaging as a Tool in the Design and Validation of a Novel Intelligent Amputee Socket. Computational Methods in Applied Sciences, 19, 91-112.Springer Nature. doi: 10.1007/978-94-007-0011-6_5.

Guenther, M., & Fiedler, G. (2010). Schnittstelle Mensch-Prothese: Ansätze zur Schaftoptimierung [Humanprosthesis interface: approaches for socket optimization]. Orthopädie-Technik, 10(7), 524-528.

Papaioannou, G., Mitrogiannis, C., Nianios, G., & Fiedler, G. (2010). Assessment of amputee socket-stump-residual bone kinematics during strenuous activities using Dynamic Roentgen Stereogrammetric Analysis. J Biomech, 43(5), 871-878.Elsevier. doi: 10.1016/j.jbiomech.2009.11.013.

Papaioannou, G., Mitrogiannis, C., Nianios, G., & Fiedler, G. (2010). Assessment of Internal and External Prosthesis Kinematics during Strenuous Activities Using Dynamic Roentgen Stereophotogrammetric Analysis. JPO Journal of Prosthetics and Orthotics, 22(2), 91-105.Wolters Kluwer. doi: 10.1097/jpo.0b013e3181cca7bb.

Fiedler, G., Papaioannou, G., Mitrogiannis, C., Nianios, G., & Kyprianou, T. (2009). Development of a new Bed System with Improved Decubitus Prophylaxis for Bed-Ridden Patients. 2009 9th International Conference on Information Technology and Applications in Biomedicine, 1, (pp. 1-4).Institute of Electrical and Electronics Engineers (IEEE).Larnaca, Cyprus. doi: 10.1109/itab.2009.5394379.

Research interests

artificial limbs
mobile gait analysis
prosthesis alignment
prosthesis-integrated load cells