Quantifying arm nonuse in individuals poststroke.
BACKGROUND
Arm nonuse, defined as the difference between what the individual can do when constrained to use the paretic arm and what the individual does when given a free choice to use either arm, has not yet been quantified in individuals poststroke.


OBJECTIVE
(1) To quantify nonuse poststroke and (2) to develop and test a novel, simple, objective, reliable, and valid instrument, the Bilateral Arm Reaching Test (BART), to quantify arm use and nonuse poststroke.


METHODS
First, we quantify nonuse with the Quality of Movement (QOM) subscale of the Actual Amount of Use Test (AAUT) by subtracting the AAUT QOM score in the spontaneous use condition from the AAUT QOM score in a subsequent constrained use condition. Second, we quantify arm use and nonuse with BART by comparing reaching performance to visual targets projected over a 2D horizontal hemi-work space in a spontaneous-use condition (in which participants are free to use either arm at each trial) with reaching performance in a constrained-use condition.


RESULTS
All participants (N = 24) with chronic stroke and with mild to moderate impairment exhibited nonuse with the AAUT QOM. Nonuse with BART had excellent test-retest reliability and good external validity.


CONCLUSIONS
BART is the first instrument that can be used repeatedly and practically in the clinic to quantify the effects of neurorehabilitation on arm use and nonuse and in the laboratory for advancing theoretical knowledge about the recovery of arm use and the development of nonuse and "learned nonuse" after stroke.
University of Southern California, Los Angeles, CA 90089-9006, USA.
Cheol E
CE
Han
Sujin
S
Kim
Shuya
S
Chen
Yi-Hsuan
YH
Lai
Jeong-Yoon
JY
Lee
Rieko
R
Osu
Carolee J
CJ
Winstein
Nicolas
N
Schweighofer
D000368:Aged; D001132:Arm / Q000503:physiopathology*; D004185:Disability Evaluation; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology*; D017063:Outcome Assessment, Health Care; D011597:Psychomotor Performance / Q000502:physiology*; D015203:Reproducibility of Results; D020521:Stroke / Q000473:pathology*; D000071939:Stroke Rehabilitation
hemiparesis; outcomes assessment; physical therapy; stroke rehabilitation; upper extremity