The incidence of occult paraumbilical hernias in patients undergoing primary umbilical hernia repair.

Purpose: The primary goal of this study was to determine the incidence of occult paraumbilical hernias during open primary umbilical hernia repair. The secondary objective was to further characterize the clinical features of these patients and hernias.
Methods: This was a retrospective chart review of patients undergoing primary umbilical hernia repair at Shouldice Hospital, from 2007 to 2017. Inclusion criteria were utilized to elucidate patients, where a concomitant occult paraumbilical hernia was found. Descriptive statistics were used throughout.
Results: 5850 patients underwent primary umbilical hernia repair, 459 (7.85%) patients had concomitant primary umbilical and paraumbilical hernias. There was a preoperative suspicion/diagnosis of a paraumbilical hernia in 166 (2.8%) of these patients. In 293 (5.01%) patients who had open primary umbilical hernia repair, at least one associated occult paraumbilical defect was found during surgery. Most of umbilical and concomitant occult paraumbilical hernias were small and medium size defects. The great majority of the reported occult paraumbilical hernias were found in the supraumbilical position at a distance of 3 cm or less from the top of the umbilical defect.
Conclusion: The incidence of concomitant occult paraumbilical hernias in patients mildly overweight undergoing primary umbilical hernia repair is 5.01%, relevant to surgical decision-making. Since the great majority of these paraumbilical defects are superior to the umbilical defect, an adequate incision and dissection for at least 3 cm above the umbilical hernia may reduce the number of missed concomitant hernias and result in less presumed recurrences.