L16 Inguinal Canal PDF

L16: INGUINAL CANAL Development of the testis During development: gonads descend From posterior abdominal wall to the pelvis in females and to the scrotum in males. Processus vaginalis A tubular process of peritoneum. Passes into the scrotum with the descending testis. Its neck is usually closed at...

L16: INGUINAL CANAL Development of the testis During development: gonads descend From posterior abdominal wall to the pelvis in females and to the scrotum in males. Processus vaginalis A tubular process of peritoneum. Passes into the scrotum with the descending testis. Its neck is usually closed at the time of birth. Failure of closure → hernia. Its distal part remains as the tunica vaginalis of the testis. Inguinal (Poupart's) ligament: Is the thickened lower free border of the external oblique aponeurosis. Extends between the pubic tubercle and the anterior superior iliac spine. Laterally: Gives attachment to 2 muscles: the internal oblique and transverse abdominis. Has an under-curving fibrous fibrous band. A triangular deficiency in the external oblique aponeurosis. Located above and medial to pubic tubercle. Boundaries: - Apex: Points laterally - Base: pubic crest - Borders: Lateral and medial crura of the aponeurosis of the external oblique. Deep inguinal ring: A deficiency in transversalis fascia. Located 1/2 inch above the midpoint of the inguinal ligament ▪ The deep inguinal ring is an oval opening in the fascia transversalis, ▪ The superficial inguinal ring is a triangular gap in the external oblique aponeurosis. It is shaped like an obtuse angled triangle. The base of the triangle is formed by the pubic crest. Inguinal canal : DEFINITION ▪ This is an oblique intermuscular passage in the lower part of the anterior abdominal wall, situated just above the medial half of the inguinal ligament. The inguinal canal extends from the deep inguinal ring to the superficial inguinal ring. Oblique path through the anterior abdominal wall extending from the deep to the superficial inguinal rings. Lies parallel and superior to the medial half of the inguinal ligament. The inguinal canal is larger in males than in females Anterior wall of the Inguinal Canal: External oblique aponeurosis Internal oblique re-enforces laterally. Remember! - Internal oblique arises from the lateral 2/3rd of the inguinal ligament. - Deep inguinal ring is located just above the midpoint of the inguinal ligament. - Transverse abdominis arises from the lateral of the inguinal ligament → does not contribute to the anterior wall. Roof Wall of the Inguinal Canal: The inferior arching fibers of the internal oblique and transverse abdominis, arising from the inguinal ligament It is formed by the arched fibers of the internal oblique and transversus abdominis muscles. Posterior wall of the Inguinal Canal: Medial half: - Conjoint tendon - Reflected part of the inguinal ligament. Lateral half: - Transversalis fascia. The inferior epigastric artery ascends in the posterior wall of the inguinal canal medial to the deep inguinal ring to reach the rectus sheath. Contents of the Inguinal Canal: 1. Ilioinguinal nerve in both sexes. 2. Spermatic cord in the male: Is formed when the testis descends through the inguinal canal into the scrotum carrying its duct, vessels and nerves. 3. Round ligament of the uterus in the female. Indirect inguinal hernia :Common in young males. Called congenital inguinal hernia. The processus vaginalis has remained open Common in young males Called indirect because it extends from the deep ring and follows an oblique course through the inguinal canal. Usually extends into the scrotum Direct/ acquired Inguinal hernia: Less common than the indirect. Neck of sac lies medial to Inferior Epigastric artery Results from weakness of the posterior wall of the inguinal canal (Triangle of Hesselbach). Common after 40 years of age. The hernial sac protrudes directly forewords without passing through the deep inguinal ring