title: Reachable workspace reflects dynamometer-measured upper extremity strength in facioscapulohumeral muscular dystrophy.
abstract: BACKGROUND
  It is not known whether a reduction in reachable workspace closely reflects loss of upper extremity strength in facioscapulohumeral muscular dystrophy (FSHD). In this study we aimed to determine the relationship between reachable workspace and quantitative upper extremity strength measures.
  
  
  METHODS
  Maximal voluntary isometric contraction (MVIC) testing of bilateral elbow flexion and shoulder abduction by hand-held dynamometry was performed on 26 FSHD and 27 control subjects. In addition, Kinect sensor-based 3D reachable workspace relative surface areas (RSAs) were obtained. Loading (500-g weight) effects on reachable workspace were also evaluated.
  
  
  RESULTS
  Quantitative upper extremity strength (MVIC of elbow flexion and shoulder abduction) correlated with Kinect-acquired reachable workspace RSA (R = 0.477 for FSHD, P = 0.0003; R = 0.675 for the combined study cohort, P < 0.0001). Progressive reduction in RSA reflected worsening MVIC measures. Loading impacted the moderately weak individuals the most with additional reductions in RSA.
  
  
  CONCLUSIONS
  Reachable workspace outcome measure is reflective of upper extremity strength impairment in FSHD.
authors: Department of Physical Medicine and Rehabilitation, University of California at Davis School of Medicine, 4860 Y Street, Suite 3850, Sacramento, California, 95817, USA.
authors: Jay J
authors: JJ
authors: Han
authors: Department of Physical Medicine and Rehabilitation, University of California at Davis School of Medicine, 4860 Y Street, Suite 3850, Sacramento, California, 95817, USA.
authors: Evan
authors: E
authors: De Bie
authors: Department of Physical Medicine and Rehabilitation, University of California at Davis School of Medicine, 4860 Y Street, Suite 3850, Sacramento, California, 95817, USA.
authors: Alina
authors: A
authors: Nicorici
authors: Department of Physical Medicine and Rehabilitation, University of California at Davis School of Medicine, 4860 Y Street, Suite 3850, Sacramento, California, 95817, USA.
authors: Richard T
authors: RT
authors: Abresch
authors: Department of Electrical Engineering and Computer Sciences, University of California at Berkeley College of Engineering, Berkeley, California, USA.
authors: Ruzena
authors: R
authors: Bajcsy
authors: Department of Physical Medicine and Rehabilitation, University of California at Davis School of Medicine, 4860 Y Street, Suite 3850, Sacramento, California, 95817, USA.|Department of Electrical Engineering and Computer Sciences, University of California at Berkeley College of Engineering, Berkeley, California, USA.
authors: Gregorij
authors: G
authors: Kurillo
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D016022:Case-Control Studies; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007537:Isometric Contraction; D008297:Male; D008875:Middle Aged; D009068:Movement; D053580:Muscle Strength / Q000502:physiology*; D053581:Muscle Strength Dynamometer; D020391:Muscular Dystrophy, Facioscapulohumeral / Q000175:diagnosis* / Q000503:physiopathology*; D016059:Range of Motion, Articular / Q000502:physiology; D058998:Remote Sensing Technology / Q000295:instrumentation*; D015203:Reproducibility of Results; D013223:Statistics as Topic; D034941:Upper Extremity / Q000503:physiopathology*; D055815:Young Adult
keywords: FSHD; Kinect; dynamometry; reachable workspace; upper extremity