Validation of the Leap Motion Controller using markered motion capture technology.
The Leap Motion Controller (LMC) is a low-cost, markerless motion capture device that tracks hand, wrist and forearm position. Integration of this technology into healthcare applications has begun to occur rapidly, making validation of the LMC׳s data output an important research goal. Here, we perform a detailed evaluation of the kinematic data output from the LMC, and validate this output against gold-standard, markered motion capture technology. We instructed subjects to perform three clinically-relevant wrist (flexion/extension, radial/ulnar deviation) and forearm (pronation/supination) movements. The movements were simultaneously tracked using both the LMC and a marker-based motion capture system from Motion Analysis Corporation (MAC). Adjusting for known inconsistencies in the LMC sampling frequency, we compared simultaneously acquired LMC and MAC data by performing Pearson׳s correlation (r) and root mean square error (RMSE). Wrist flexion/extension and radial/ulnar deviation showed good overall agreement (r=0.95; RMSE=11.6°, and r=0.92; RMSE=12.4°, respectively) with the MAC system. However, when tracking forearm pronation/supination, there were serious inconsistencies in reported joint angles (r=0.79; RMSE=38.4°). Hand posture significantly influenced the quality of wrist deviation (P<0.005) and forearm supination/pronation (P<0.001), but not wrist flexion/extension (P=0.29). We conclude that the LMC is capable of providing data that are clinically meaningful for wrist flexion/extension, and perhaps wrist deviation. It cannot yet return clinically meaningful data for measuring forearm pronation/supination. Future studies should continue to validate the LMC as updated versions of their software are developed.
Department of Telemedicine and Virtual Rehabilitation, Burke Medical Research Institute, White Plains, NY, USA; Department of Rehabilitation Medicine, Weill-Cornell Medical College, New York, NY, USA.
Anna H
AH
Smeragliuolo
Motor Recovery Laboratory, Burke Medical Research Institute, White Plains, NY, USA.
N Jeremy
NJ
Hill
The City College of New York, School of Biomedical Engineering, New York, NY, USA.
Luis
L
Disla
Department of Telemedicine and Virtual Rehabilitation, Burke Medical Research Institute, White Plains, NY, USA; Department of Rehabilitation Medicine, Weill-Cornell Medical College, New York, NY, USA. Electronic address: dap3002@med.cornell.edu.
David
D
Putrino
D000328:Adult; D001696:Biomechanical Phenomena; D005260:Female; D005542:Forearm / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology*; D011403:Pronation; D011884:Radius / Q000502:physiology; D013484:Supination; D017216:Telemedicine / Q000295:instrumentation*; D014457:Ulna / Q000502:physiology; D014953:Wrist / Q000502:physiology*; D014955:Wrist Joint / Q000502:physiology; D055815:Young Adult
Leap motion; Motion capture; Motor recovery; Physical therapy; Rehabilitation; Telemedicine