Contralateral metachronous inguinal hernias in adults: role for prophylaxis during the TEP repair

Contralateral exploration during laparoscopic totally extraperitoneal (TEP) inguinal herniorrhaphy allows for the repair of incidentally found hernias. Nonetheless, some patients with a negative contralateral exploration subsequently develop a symptomatic hernia on that side. We pondered the incidence of contralateral metachronous hernia development and whether prophylactic "repair" in these circumstances would be beneficial. A retrospective analysis of patients who underwent laparoscopic TEP exploration at our institution was performed. Demographic, operative and follow-up information was obtained through medical record review, physical examination and telephone/mailed survey. From 1995 to 2009, a total of 1,479 inguinal herniorrhaphies on 976 patients were performed by a single staff surgeon. Bilateral exploration was completed in 923 (95%) of these patients, of whom bilateral repair was performed on 503 (55%). The study cohort comprises the 409 (42%) patients having a unilateral repair with a negative contralateral exploration and no previous contralateral hernia repair (n = 11). With a median follow-up of 5.9 years (range 0-14), 33 (8.1%) hernias developed on the previously "healthy" side, yielding incidence rates at 1, 5 and 10 years of 1.6, 5.9 and 11.8%, respectively. The median time to hernia development was 3.7 years (range 0.1-12.4). Of the 30 inguinal hernias that have been repaired, 25 (83%), 3 (10%) and 2 (7%) were of indirect, direct and pantaloon types, respectively. When considering prophylactic repair during TEP explorations, a yearly risk of 1.2% of developing a contralateral hernia after negative exploration needs to be balanced against the low but potential risk of groin pain following prophylactic repair.