Inguinal Neuritis in Open Recurrent Hernia Repair

PURPOSE: To investigate the pattern of occurrence of inguinal neuritis in recurrent inguinal hernia. We hypothesize that neuritis will occur in more nerves with a wider distribution than in primary repair. METHODS: Retrospective chart review of thirty consecutive recurrent inguinal hernia repairs concentrating on the occurrence of inguinal neuritis. These are not chronic pain patients. Nerves suspected of containing inguinal neuritis were sent for histologic examination. Ilioinguinal nerves were routinely resected. Operative parameters and nerve pathology reports were reviewed. These data were compared with a recent series of one hundred consecutive primary inguinal hernia repairs with a 34% incidence of inguinal neuritis. An independent statistician from Whitman University reviewed the data. RESULTS: Twenty patients were found to have inguinal neuritis among thirty recurrent open inguinal hernia repairs (66%). This compares to 34% among primary repairs, but it is a similar rate (P > 0.42) assuming that the damaged nerve was left intact in 34% of these recurrences during the primary repair. In recurrent inguinal hernia 69% of neuritis occurred in the ilioinguinal nerve compared to 88% of damaged ilioinguinal nerves in the primary hernia. A test for the difference in proportions gives P > 0.10. The most common site of neuritis occurrence in recurrent hernias with nerve damage to the ilioinguinal nerve was at the external oblique neuroperforatum among 70% of patients compared to 83% in primary cases. A test for difference in proportions gives P > 0.36. Two separate nerves were found to exhibit neuritis in six patients (20%) significantly higher than 1% among primary hernias (P < 0.01). CONCLUSION: The overall incidence of inguinal neuritis was 66% in recurrent inguinal hernia repairs. The ilioinguinal nerve was most commonly affected in these recurrent hernias. Inguinal neuritis occurs more commonly in recurrent hernia compared with primary inguinal hernia; however, it has a similar distribution. Neuritis occurs in two nerves with 20% frequency (P < 0.01), so all nerves should be assessed during recurrent herniorrhaphy. The data support the hypothesis.