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Are Nerves Left In Situ Associated With Less Chronic Pain Than Manipulation During Inguinal Hernia Repair?
Emily George1, Molly A Olson2, Benjamin K Poulose1
1Department of Surgery, The Ohio State University Wexner Medical Center, Columbus, Ohio.
Introduction:
Nerve damage has been implicated in chronic groin pain, particularly iliohypogastric, ilioinguinal, and genital branches of genitofemoral nerves. We investigated whether three nerve identification (3N) and preservation is associated with decreased pain 6 mo after hernia repair compared to two common strategies of nerve management: ilioinguinal nerve identification (1N) and two nerve identification (2N).
Methods:
We identified adult inguinal hernia patients within the Abdominal Core Health Quality Collaborative national database. Six-month postoperative pain was defined using the EuraHS Quality of Life tool. A proportional odds model was used to estimate odds ratios (ORs) and expected mean differences in 6-month pain for nerve management while adjusting for confounders identified a priori.
Results:
Four thousand four hundred fifty one participants were analyzed; 358 (3N), 1731 (1N), and 2362 (2N) consisting mostly of White males (84%) over the age of 60 y old. Academic centers identified all three nerves more often than ilioinguinal or two nerve identification methods. Median 6-month postoperative pain scores were 0 [interquartile range 0-2] for all nerve management groups (P = 0.51 3N versus 1N and 3N versus 2N). There was no evidence of a difference in the odds of higher 6-month pain score in nerve management methods after adjustment (3N versus 1N OR: 0.95; 95% confidence interval 0.36-1.95, 3N versus 2N OR: 1.00; 95% confidence interval 0.50-1.85).
Conclusions:
Although guidelines emphasize three nerve preservation, the management strategies evaluated were not associated with statistically significant differences in pain 6 mo after operation. These findings suggest that nerve manipulation may not contribute as a significant role in chronic groin pain after open inguinal hernia repair.

