The Clinician's Guide to Computer Vision in the Motion Capture Galaxy.

In keeping with the topic of this special issue, "Breakthroughs in Stroke Rehabilitation: Bridging Engineering, Neuroscience, and Motor Control," this commentary addresses the recent emergence of computer vision motion capture (CVMC, aka markerless motion capture) with a realistic check-in on its current measurement performance and future utility as a clinical assessment tool. These are heady times. It would be understandable to misinterpret early demonstrations of CVMC in clinical research as a suggestion that this innovative tool is ready for clinical deployment. In reality, benchmarks for CVMC measurements are still being established, and cultivation of targeted clinical practice approaches informed by motion analysis remains aspirational. In this commentary, we reframe the CVMC conversation by first acknowledging the current state of CVMC as a technology still in development. We then consider the path to a long-term goal: targeted stroke rehabilitation in clinical practice informed by the quantification of movement function. In lighthearted spirit, we channel Douglas Adams' book series, "The Hitchhikers Guide to the Galaxy" (HG2G; Adams, 1979-1992), providing clinician hitchhikers some recommendations to deftly navigate the CVMC landscape on their intergalactic motion capture travels between lab and clinic. And so, just as Ford Prefect, the friendly alien researcher in the HG2G book series would say to reassure new hitchhikers:"You just come along with me and have a good time. The Motion Capture Galaxy's a fun place. You'll need to have a fish in your ear."- Ford Prefect (adapted from Adams; Book 1, Chapter 5).