Control within a virtual environment is correlated to functional outcomes when using a physical prosthesis.

The study included only nine people with transhumeral amputations and prior targeted muscle reinnervation, so it says little about other amputation levels or people without that surgery. All participants received occupational therapy, custom pattern recognition prosthesis fitting, home use, practice and recalibration in one sequence, so the contribution of any single component cannot be separated. Pre-home-trial virtual outcome data were available for only six of nine participants because two had prior virtual prosthesis experience and data from one subject were lost. The authors state that correlation does not imply causation and that this study cannot show virtual practice transfers to better functional outcomes. Virtual test difficulty can change with allowed time, number of limb movements, movement distance and matching tolerance, so results may not transfer across test settings. Home wear time was variable, and one participant's wear time could not be accurately determined because the prosthesis was removed while powered on.

No conflict-of-interest or funding statement is included in the supplied text. The publication record lists U.S. Government Non-P.H.S. research support.

Do not conclude that virtual environment practice improves physical prosthesis function. The study found correlations after a 6-week home trial that also included occupational therapy, custom pattern recognition prosthesis fitting, home use, practice and recalibration, and the authors state that correlation does not imply causation.