Journal of NeuroEngineering and Rehabilitation

RESEARCH Open Access Control within a virtual environment is correlated to functional outcomes when using a physical prosthesis Levi Hargrove 1,2* , Laura Miller 1,2 , Kristi Turner 1 and Todd Kuiken 1,2 From Second World Congress hosted by the American Orthotic & Prosthetic Association (AOPA) Las Vegas, NV, USA. 06-09 September 2017 Abstract Background: Advances such as targeted muscle reinnervation and pattern recognition control may provide improved control of upper limb myoelectric prostheses, but evaluating user function remains challenging. Virtual environments are cost-effective and immersive tools that are increasingly used to provide practice and evaluate prosthesis control, but the relationship between virtual and physical outcomes — i.e., whether practice in a virtual environment translates to improved physical performance — is not understood. Methods: Nine people with transhumeral amputations who previously had targeted muscle reinnervation surgery were fitted with a myoelectric prosthesis comprising a commercially available elbow, wrist, terminal device, and pattern recognition control system. Virtual and physical outcome measures were obtained before and after a 6-week home trial of the prosthesis. Results: After the home trial, subjects showed statistically significant improvements ( p < 0.05) in offline classification error, the virtual Target Achievement Control test, and the physical Southampton Hand Assessment Procedure and Box and Blocks Test. A trend toward improvement was also observed in the physical Clothespin Relocation task and Jebsen-Taylor test; however, these changes were not statistically significant. The median completion time in the virtual test correlated strongly and significantly with the Southampton Hand Assessment Procedure ( p = 0.05, R = − 0.86), Box and Blocks Test ( p = 0.007, R = − 0.82), Jebsen-Taylor Test ( p = 0.003, R = 0.87), and the Assessment of Capacity for Myoelectric Control ( p = 0.005, R = − 0.85). The classification error performance only had a significant correlation with the Clothespin Relocation Test ( p = 0.018, R = .76). Conclusions: In-home practice with a pattern recognition-controlled prosthesis improves functional control, as measured by both virtual and physical outcome measures. However, virtual measures need to be validated and standardized to ensure reliability in a clinical or research setting. Trial registration: This is a registered clinical trial: NCT03097978 . Keywords: Prosthetics, Myoelectric control, Pattern recognition, Outcomes * Correspondence: l-hargrove@northwestern.edu 1 Shirley Ryan AbilityLab, 355 E. Erie Street, Chicago, IL 60611, USA 2 Departments of Physical Medicine and Rehabilitation and Biomedical Engineering, Northwestern University, 663 Clark St, Evanston, IL 60208, USA © The Author(s). 2018 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License ( http://creativecommons.org/licenses/by/4.0/ ) , which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver ( http://creativecommons.org/publicdomain/zero/1.0/ ) applies to the data made available in this article, unless otherwise stated. Hargrove et al. Journal of NeuroEngineering and Rehabilitation 2018, 15 (Suppl 1):60 https://doi.org/10.1186/s12984-018-0402-y