Influence of sensory and proprioceptive impairment on the development of phantom limb syndrome during regional anesthesia.
BACKGROUND
The relation between impairment of sensorimotor function and occurrence of phantom limb syndrome (PLS) during regional anesthesia has not been described. This study assessed the temporal relation between PLS and the progression of sensorimotor impairment during placement of a brachial plexus nerve block.


METHODS
Fifty-two patients had their arm randomly placed either alongside their body (group A) or in 90 degrees abduction (group B) immediately after brachial plexus nerve block placement. Responses to pin prick, cold, heat, touch, proprioception, and voluntary movement were assessed every 5 min for 60 min. Meanwhile, patients described their perceptions of the size, shape, and position of their anesthetized limb.


RESULTS
Phantom limb syndrome occurred 19 +/- 9 min after nerve block placement. Proprioception was impaired and abolished after 22 +/- 9 and 43 +/- 17 min, respectively (P < 0.05 vs. PLS onset). When PLS occurred, responses to pin prick, cold, heat, and proprioception were abolished in 96, 94, 87, and 4% of patients, respectively. Patients were more likely to feel their anesthetized limb in adduction and in abduction in groups A and B (P < 0.05 vs. group A), respectively. After PLS had become motionless, two stereotyped positions were identified: arm adduction, elbow flexion, hand over the abdomen (68% of group A patients) and arm abduction, elbow flexion, hand held close to the homolateral ear (48% of group B patients).


CONCLUSIONS
This study provides a better understanding of the determinants of PLS by showing that the final position of PLS is related both to the abolition of proprioception and the initial position of the anesthetized limb.
Paqueron
Xavier
X
Department of Anesthesiology, Centre Hospitalier Universitaire Pitié-Salpêtrière, Paris, France. xavier.paqueron@psl.ap-hop-paris.fr
Leguen
Morgan
M
Gentili
Marc E
ME
Riou
Bruno
B
Coriat
Pierre
P
Willer
Jean Claude
JC
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001917:Brachial Plexus / Q000502:physiology*; D005260:Female; D006801:Humans; D007866:Leg / Q000294:innervation*; D008297:Male; D008875:Middle Aged; D009407:Nerve Block / Q000009:adverse effects*; D010465:Perception; D011187:Posture; D012678:Sensation Disorders / Q000209:etiology*; D013577:Syndrome