The Biology and Anatomy of Inguinofemoral Hernia.

The purpose of this article is to discuss the biology of hernia and covers such features as the male predominance of hernia, the causal significance of a patent processus vaginalis, the effect of the shape of the skeleton on liability to the development of hernia, and the alterations in collagen structure and metabolism that may be involved in the genesis of hernia. In addition, the influence of such factors as peritoneal dialysis, appendectomy, and pregnancy are reviewed. The anatomy of the groin is outlined in detail. The lower abdominal region is a layered structure; the defect in musculoaponeurotic continuity that leads to a hernia exists only in the transversus abdominis layer. The external oblique and internal oblique layers are not primarily involved in the genesis of hernia. The major structures within the transversus abdominis layer are described and illustrated including the deep inguinal ring, iliopubic tract, transversus abdominis arch, femoral sheath, and Cooper's ligament. The structure of the inguinal canal and spermatic cord, and the continuities of investing fascia from the abdominal wall to the spermatic cord are also described in detail. The essential features of anatomic repair of groin hernias are reviewed. Anatomic repairs are always conducted within the transversus abdominis lamina. The structures that need to be apposed in primary repair are specified.