Reflex sympathetic dystrophy of the left hand and motor impairments of the unaffected right hand: impaired central motor processing?
OBJECTIVE
To test whether central motor processing can be impaired in chronic reflex sympathetic dystrophy (RSD).


METHODS
Experimental 2-group analysis.


METHODS
Tertiary care center in the Netherlands.


METHODS
Five patients with stage 3 RSD of the left forearm, free of symptoms and complaints in the right forearm; and 10 healthy control subjects.


METHODS
On a digitizer, RSD patients and controls had to draw 3 sequences of graphemes of different complexity with their (unaffected) dominant right hand. The drawing tracks were segmented in time periods between points of velocity minima of the pen tip.


METHODS
Mean velocity, coefficients of variation of both length and movement time per segment, and mean intersegmental pausing time were calculated for each sequence.


RESULTS
A repeated-measures analysis of variance by using the multivariate method yielded a 35% lower mean velocity (F(1,13) = 5.83, P =.031), a 110% larger segment length variability (F(1,13) = 9.72, P =.008) and a 60% larger variability of movement time per segment (F(1,13) = 5.78, P =.032) in RSD patients. No group difference was found for intersegmental pausing time or any interaction effect with the type of task.


CONCLUSIONS
Patients with chronic RSD have a normal ability to preprogram sequential movements of their unaffected hand; but with impaired temporospatial coding and movement execution. We concluded that cortical mechanisms may be involved in motor impairments in patients with chronic RSD.
Ribbers
Gerard M
GM
Rehabilitation Center Rijndam and Institute of Rehabilitation of the Erasmus University Center Rotterdam, The Netherlands. gmr@igr.nl
Mulder
Theo
T
Geurts
Alexander C
AC
den Otter
Rob A
RA
D000328:Adult; D000704:Analysis of Variance; D001696:Biomechanical Phenomena; D016022:Case-Control Studies; D002493:Central Nervous System Diseases / Q000503:physiopathology; D005260:Female; D006225:Hand / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009069:Movement Disorders / Q000503:physiopathology*; D012019:Reflex Sympathetic Dystrophy / Q000503:physiopathology*