It has been demonstrated that motility disorders may be responsible for esophageal and colon diverticulosis. Recently anatomic alterations of both small bowel muscular layers and myenteric plexus have been described in patients with small bowel diverticulosis. Such pathological features could be responsible for motility disorders and small bowel diverticulosis formation. The aim of this work was to study the small bowel motility in patients with small bowel diverticulosis. Ten patients (mean age: 69.2 +/- 6 years mean +/- SEM) with more than 3 diverticula in the jejunum or the ileum (excepting duodenal diverticulum) were studied. After an overnight fast, a 4 lumen probe (side holes 10 cm apart) was used to record duodeno-jejunal motility for 4 hours. Esophageal manometry was also performed in 8 patients. The mean number of phase 3 of the migrating motor complex (mean +/- SEM) during 4 hours was significantly lower in patients with small bowel diverticulosis (0.15 +/- 0.05/hours; mean +/- SEM) than in 10 normal volunteers (0.52 +/- 0.07/hours; mean +/- SEM) (P less than 0.01); 5 patients had zero phase 3 during the 4 hours of recording; one patient displayed intestinal hypomotility associated with aberrant phase 3 like activity; 4 patients showed simultaneous minute-rhythm during more than 80 percent of the phase 2 of the migrating motor complex. Esophageal manometry was also disturbed in 6 patients (low amplitude contractions less than 30 cm H2O in the distal esophagus). Bacterial overgrowth was investigated in 8 patients by means of a glucose breath-test and was found in 6 cases. In conclusion, duodeno jejunal motility is altered in patients with small bowel diverticulosis.(ABSTRACT TRUNCATED AT 250 WORDS)