Histological findings of the internal inguinal ring in patients having indirect inguinal hernia.

Background: Aiming to deepen the understanding of the factors involved in the genesis of groin hernia, this study is focused on identifying the histological changes within the muscle fibers of the internal inguinal ring in patients having indirect inguinal hernia.

Methods: In eight patients with primary or recurrent bilateral indirect inguinal hernia who underwent a Stoppa open posterior inguinal hernia repair, a tissue specimen from the edge of the internal inguinal ring was biopsied and histologically examined.

Results: In all of the tissue samples, remarkable degenerative changes such as fibrohyaline degeneration of the muscle fibers, vascular congestion, and phlogistic infiltration through lymphohistiocytary elements was constantly detected. Also, in the patients with recurrent hernia, the key characteristic of the muscular change was that of fibrohyaline and, occasionally, myxoid degeneration of the myocytes. Nerve endings were frequently detected within the muscular structures of the internal inguinal ring.

Conclusion: The degenerative fibrohyaline alteration, as well as the evidence of phlogistic elements within the examined structures, could represent a reason for a contractile incompetence of the internal inguinal ring. Consequently, the described findings lead the authors to depict this inflammatory degenerative structural weakness of the internal inguinal ring as a possible culprit of indirect inguinal hernia formation.