Should occult hernia be repaired in TAPP?

Occult hernias, defined as asymptomatic hernias not detectable on physical examination, are identified intraoperatively in up to 22% of patients undergoing laparoscopic inguinal hernia repair. While treatment may prevent future symptomatic herniation in approximately 21-29% of patients, the risk of complications on the occult hernia side remains unclear, especially when using the transabdominal preperitoneal (TAPP) approach, which has been widely adopted.

We retrospectively analyzed 350 patients who underwent elective TAPP repair between January 2020 and December 2024. Patients were divided into two groups: the occult hernia group (n = 51), who underwent bilateral repair, including occult hernia treatment, and the non-occult hernia group (n = 299), who received unilateral repair without occult hernia identification. Postoperative complications were assessed at the first outpatient visit (median, 19 days postoperatively), compared between groups, and analyzed by occult and symptomatic sides.

The overall complication rates, defined as the occurrence of seroma; surgical site infection; and acute postoperative inguinal pain (APIP), which is pain requiring analgesics, were 13.7% and 16.4% in the occult and non-occult hernia groups, respectively (p = 0.84). On the occult hernia side (n = 51), the complication rate (seroma and APIP) was significantly lower than on the symptomatic side (n = 350) (2.0% vs. 12.3%, p = 0.03), with only one seroma and no APIP observed.

Based on prior reports, the number needed to treat to prevent one symptomatic hernia was estimated to be 4.6 (95% credible interval: 3.1-7.3), while the number needed to harm for occult hernia side complications was 51. Treatment of occult hernias during TAPP repair was associated with a low incidence of complications on the occult hernia side and a favorable benefit-to-risk balance. These findings support the safety and rationale for treating occult hernias in TAPP procedures.