Cooperative Hernia Study

BACKGROUND: The Cooperative Hernia Study assessed postoperative pain in a prospective trial as part of a larger study looking at the recurrence rate and other morbidity of the Bassini, McVay, and Shouldice repairs. METHODS: Patients were randomized to one of three surgical hernia repairs. Patients were seen in follow-up at 6, 12, and 24 months and were assessed for the presence of pain, numbness, paresthesia, and recurrence. RESULTS: Three hundred fifteen patients were seen in follow-up, with 276 seen at the 2-year mark. At 1 year, 62.9% of patients had groin or inguinal pain and 11.9% of patients had moderate to severe pain; 53.6% had pain and 10.6% of patients continued to report moderate to severe pain 2 years postoperatively. The predictors for long-term postoperative pain were as follows: absence of a visible bulge before the operation (p < 0.001); presence of numbness in the surgical area postoperatively (p < 0.05); and patient requirement of more than 4 weeks out of work postoperatively (p < 0.004). Three distinct chronic pains were identified. The most common and most severe pain was somatic, localized to the common ligamentous insertion to the public tubercle. The second was neuropathic and was referable to the ilioinguinal or genitofemoral nerve distribution. This was likely because of injury to the genitofemoral nerves, either at surgery or subsequently by encroachment of scar. The third pain was visceral, ejaculatory pain. Twenty-four percent of patients had postoperative numbness at 2 years, independent of the type of repair. Numbness was most common in the distribution of cutaneous branches of the ilioinguinal and iliohypogastric nerves. CONCLUSION: Pain or numbness are common late sequelae of traditional external surgical hernia repairs. Strategies need to be developed to reduce the risk of these complications.