Bilateral motor cortex disinhibition in complex regional pain syndrome (CRPS) type I of the hand.
BACKGROUND
Complex regional pain syndrome type I (CRPS I) develops as a consequence of trauma affecting the limbs, without obvious nerve lesion. Its features include pain, edema, autonomic dysfunction, movement disorder, and trophic changes. CNS involvement is suggested by the symptoms, but the pathophysiology of CRPS I is unknown.


OBJECTIVE
To assess excitability changes in the motor cortex in patients with CRPS I.


METHODS
The authors studied 25 patients with unilateral CRPS I involving the hand by means of transcranial magnetic stimulation using a paired-pulse paradigm. Motor threshold (MT) and intracortical inhibition and facilitation were determined on the affected and the clinically unaffected side. A control group of 20 healthy subjects was studied.


RESULTS
The authors found a significant reduction of intracortical inhibition on both sides of patients with CRPS compared with control subjects, whereas intracortical facilitation and MT did not differ significantly. However, in the patients' group, the presence of allodynia significantly decreased MT.


CONCLUSIONS
The authors showed a bilateral disinhibition of the motor cortex in patients with complex regional pain syndrome.
Schwenkreis
P
P
Department of Neurology, Ruhr-University Bochum, BG-Kliniken Bergmannsheil, Bochum, Germany. Peter.Schwenkreis@ruhr-uni-bochum.de
Janssen
F
F
Rommel
O
O
Pleger
B
B
Völker
B
B
Hosbach
I
I
Dertwinkel
R
R
Maier
C
C
Tegenthoff
M
M
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006225:Hand / Q000294:innervation / Q000601:surgery; D006230:Hand Injuries / Q000150:complications; D006801:Humans; D007266:Inhibition, Psychological; D008280:Magnetics; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000503:physiopathology*; D011183:Postoperative Complications / Q000503:physiopathology; D012019:Reflex Sympathetic Dystrophy / Q000209:etiology / Q000503:physiopathology*