Influence of preservation versus division of ilioinguinal, iliohypogastric and genital nerves during open mesh herniorrhaphy. Prospective multicentric study of chronic pain.

Objective: To evaluate whether the various surgical treatment reserved for ilioinguinal, iliohypogastric, and genital branch of the genitofemoral nerves, during open hernia mesh repair, is effective in reducing chronic postoperative pain. Background: Interest in chronic groin pain following herniorrhaphy has escalated, in recent years, due both to treatment and legal implications. However, much debate still exists concerning which treatment to reserve for the 3 inguinal sensory nerves. Methods: A multicentric prospective study involving 11 Italian institutions led to the recruitment of 973 cases of hernioplasty. All surgeons were asked to report whether or not each nerve had been identified and preserved or divided. The main endpoint of the study was the evaluation of moderate to severe chronic pain at 6 months and 1 year. Results: Overall, the presence of groin pain at the 6-month and 1-year follow-up was 9.7% and 4.1%, respectively. Pain was mild in 7.9% and moderate to severe in 2.1%, at 6 months, and mild in 3.6% and moderate to severe in 0.5%, at 1 year. Univariate and multivariate analysis showed that lack of identification of nerves is significantly correlated with presence of chronic pain, the risk of developing inguinal pain increasing with the number of nerves not detected. Likewise, division of nerves was clearly correlated with presence of chronic pain. Conclusions: The present findings indicate that identification and preservation of nerves during open inguinal hernia repair reduce chronic incapacitating groin pain and that, in the majority of patients with chronic pain at 6 months, the pain at 1 year is resolved only with conservative or medical treatment.