[Anatomo-surgical considerations on the inguinal region. I. The external oblique muscle].

In the light of recent publications where common hernia repair techniques are defined as unanatomical and unphysiological, a study of the anatomy of the inguinal region has been undertaken layer by layer on cadavers. The first note analyses the most superficial layer of the inguinal region, namely the external oblique muscle. Having described the dissection technique, the most significant data regarding this formation are examined. Although the correctness of the data given in anatomy textbooks is confirmed in the majority of cases, study of necroptic findings highlights a number of factors which are misunderstood or have been insufficiently analysed. Findings included vibices of the external oblique aponeurosis, to which no pathogenetic importance is attributed with respect to inguinal hernia, as well as the presence of an internal tunic of Lauth's ligament which was not easy to strip away from the posterior surface of the external oblique muscle and, finally, localization variations of the external inguinal ring. The secondary involvement of the aponeurosis of the external oblique muscle in the genesis of inguinal hernia is confirmed along with its importance as a reinforcement in hernia repair operations, the containment function proper being performed by the posterior wall. A subsequent note will deal with this.