Some observations on the functional anatomy of inguinal hernia and its bearing on the operative treatment

Abstract

ANATOMY is at the present time in a phase of activity and expansion, and surgery is both an agent and a beneficiary of this activity. A principal feature is the change from a static to a functional concept of anatomy. The change of approach in the case of inguinal hernia has, however, been slow. The operation devised by Bassini (1890) was such an FIG. 379.-The right femoral and inguinal regions viewed from the inner aspect. (After a drawing of Hamilton Russell's to illustrate his article on femoral hernia, in which incidentally the sling-like character of the transversalis fascia at the internal ring was shown.) (1943) was a pioneer in advocating re-suture of the enlarged internal ring as the essential procedure after removal of the sac in indirect inguinal hernia. Later, Lytle (1945) published important detailed anatomical studies on the internal ring. He showed that the transversalis fascia at the internal ring constitutes a sling attached laterally and that on muscular contraction this sling is pulled upwards and laterally so that the opening tends to lie under and be protected by the medial curved edge of the internal oblique as it takes origin from the inguinal ligament. The sling-like character at the internal ring had been previously recognized (e.g., HamiltonRussell, 1gz3-s~ Fig. 379), but its functional significance was not appreciated until the work of Lytle.Influenced by the work of Lytle, my own approach has been to study the functional anatomy of inguinal hernia at operation by stimulating the associated muscles by a faradic current. The results are best considered under two headings-first, the functional anatomy of indirect inguinal hernia ; and secondly, the functional anatomy of direct inguinal hernia. THE FUNCTIONAL ANATOMY OF INDIRECT INGUINAL HERNIAIf after identification and removal of the sac the margins of the internal ring are defined, and the conjoint internal oblique and transversalis muscles induced to contract by faradic stimulation, the advance on all previous operations for inguinal hernia, and the principles underlying it seemed so sound (namely, to re-constitute the posterior wall of the inguinal canal by suturing behind the cord the conjoint muscle and tendon to the upturned edge of the inguinal ligament, and thus to reconstitute the obliquity of the inguinal canal) that it long remained a standard surgical procedure, immune even from serious criticism. But the theoretical weakness of Bassini's operation was that it treated the conjoint muscle and tendon as though they were inert rather than actively functioning tissues. McGavin (~gog), Handley (1918), and Gallie and Le Mesurier (1921) recognized this, and devised the operations known after their names which aimed a t strengthening the posterior wall of the inguinal canal without distorting and maiming the conjoint muscle and tendon. Handley, and later Gallie and Le Mesurier, pointed out that such forcible distortion of the muscle was usually ineffective in that the stitches either cut out or the muscle split.More recently, the tr...

Inguinal Hernia and its Treatment

“…Ogilvie (1929) accepted the view of a muscular sphincter and considered it became incompetent from deficient muscular tone and increased intra‐abdominal pressure. Patey (1949) stimulated the exposed conjoined muscles electrically and concluded that the shutter‐like mechanism, as postulated by Keith, did not exist. He suggested that the main protective agent is a tautening of the transversalis fascia through the pull on its attachment to the deep surface of the transversalis muscle.…”

Inguinal hernia and the iliopectineal line. Deficiency of the insertion of the conjoint tendon as a factor in the aetiology, with an account of an operation for its correction and a report of 200 cases

“…It may be absent or only slightly developed, or replaced by a lateral extension of the tendon or origin of the rectus muscle; but sometimes, when it is well developed, the conjoint tendon itself is continued farther laterally as a thin expansion which reaches the medial side of the deep abdominal ring so that then no interval is present between the lower border of transversus and the inguinal ligament (Walmsley, 1939). Patey (1949) as a result of electrical stimulation of the internal oblique and transversus muscles in hernia cases makes a definite statement in his summary of the functional anatomy of inguinal hernia that the shutter-like mechanism of the conjoint tendon does not exist. Rains (1951), however, p3ints out that the shutter action of conjoint tendon can only be demonstrated when the transversus and internal oblique muscles are attached to the iliopectineal line.…”