Identification and management of the ilio-inguinal and ilio-hypogastric nerves in open inguinal hernia repair: benefits of self-gripping mesh.

ABSTRACT

PURPOSE: A large randomized, multicenter European study recently reported a reduction in early pain after open inguinal surgery when self-gripping mesh was used compared with sutured Lichtenstein repair. This secondary exploratory study is focused on the influence of nerve identification and handling on post-operative pain. METHODS: Post-operative VAS pain data and Surgical Pain Scores (SPS) from 507 patients included in this study were analyzed according to whether inguinal nerves were preserved or resected during surgery to investigate whether identification and peri-operative nerve handling impact post-operative pain. RESULTS: Preservation of the ilio-hypogastric nerve during Lichtenstein mesh repair with suture fixation was associated with significantly more post-operative pain compared with resection at each follow-up (p ≤ 0.003). This difference was not significant with self-gripping mesh repair. The decrease from baseline in post-operative VAS and SPS scores were significantly greater after self-gripping mesh repair compared to Lichtenstein repair at 1 year, but only when the ilio-hypogastric nerve was preserved (VAS scores, p = 0.009; SPS scores, p = 0.015). No such difference was observed with the ilio-inguinal nerve. When self-gripping mesh was used, preservation of the ilio-hypogastric nerve was associated with significantly greater decreases in post-operative pain (change in VAS score from baseline) compared with Lichtenstein repair at each follow-up (p ≤ 0.018). CONCLUSIONS: The ilio-hypogastric nerve is in danger of being traumatized during Lichtenstein mesh repair with suture fixation. The use of self-gripping mesh was shown to reduce the level of post-operative pain when the ilio-hypogastric nerve was preserved. Resection of the ilio-hypogastric nerve during Lichtenstein repair eliminates this difference.