The aim of this study was to describe (during the fasting state in two patients the motor activity of the limb in Roux-en-Y hepatico-jejunostomy). In the two patients, the limb was created 15 years and 15 days prior to the study respectively. Recordings were performed with a low compliance pneumohydraulic system below the jejuno-jejunal anastomosis then in the limb. Motor studies in the limb were coupled with recordings carried out in the duodenum. In both patients, the regular occurrence of a typical phase III (PIII) activity was demonstrated in the limb whereas no retrograde or abnormal motor patterns were found. PIIIs in the limb were uncoordinated with duodenal PIIIs. Trimebutine, given intravenously, induced a typical PIII activity in the duodenum and the limb simultaneously. Spontaneous or trimebutine-induced PIIIs in the limb had a slower migration velocity (p less than 0.01) than duodenal PIIIs. Lastly, we were unable to record PIIIs in the distal jejunum below the jejuno-jejunal anastomosis despite the lack of associated abnormal motor patterns. This study demonstrates that a normally propagated PIII activity can be observed in the limb in Roux-en-Y hepatico-jejunostomy immediately or several years after the surgical procedure.