Inguinal Region PDF

Inguinal Region DPM PROGRAM Learning Objectives: 1. Describe the organization and contents of the inguinal canal in females and males. 2. Describe the course and contents of the spermatic cord. 3. Describe the descent of the testes and formation of the spermatic cord in relation to the inguinal can...

Inguinal Region DPM PROGRAM Learning Objectives: 1. Describe the organization and contents of the inguinal canal in females and males. 2. Describe the course and contents of the spermatic cord. 3. Describe the descent of the testes and formation of the spermatic cord in relation to the inguinal canal. 4. List the coverings of the spermatic cord in relation to the abdominal wall layers. 5. Discuss the difference between indirect inguinal hernias and their relationship to the inferior epigastric vessels and deep inguinal ring. 6. Discuss the difference between direct inguinal hernias and their relationship to the inferior epigastric vessels and deep inguinal ring. 7. Define the boundaries of the inguinal (Hesselbach's) triangle through which direct hernias pass. 8. Distinguish inguinal and femoral hernias. 9. Define hydrocele, hematocele, and varicocele. 1 SMU - Internal Data Describe the organization of the inguinal canal in females and males. Inguinal canal is a passageway extends medially and inferiorly, just superior and parallel to the medial half of inguinal ligament. Boundaries: Anterior wall -formed by fibers of external abdominal oblique and complemented laterally by the internal abdominal oblique muscle Posterior wall -formed laterally by transversalis fascia and parietal peritoneum (weak area) -medially by conjoint tendon (strong area) Roof -formed by arching fibers of internal abdominal oblique and transversus abdominis muscles Floor -formed by inguinal ligament -medially by the lacunar ligament Deep inguinal ring -Begins laterally at the deep ring (formed by reflection of transversalis fascia just lateral to the inferior epigastric vessels) Superficial inguinal ring -ends medially at the superficial ring (formed by an opening in the aponeurosis of external abdominal oblique muscle) -opening bounded by the lateral and medial crura fibers 2 SMU - Internal Data Describe the contents of the inguinal canal in females and males. Inguinal Canal Contents enter the deep inguinal ring and exits through the superficial inguinal ring: In males: -Spermatic cord, which contains: - pampiniform plexus of veins - testicular artery - ductus deferens & deferential artery - genital branch of genitofemoral n. - cremasteric a. - postsynaptic sympathetics - lymphatics Spermatic cord In females: -Round ligament of the uterus -remnant of the gubernaculum, connecting the uterus to the labium majus. -The round ligament presents as a tubular collection of adipose tissue NOTE: the ilioinguinal nerve (L1) emerges from the superficial ring but does not run the length of the canal SMU - Internal Data Round ligament 3 Describe the descent of the testes and formation of the spermatic cord in relation to the inguinal canal. Developmentally, the undifferentiated gonads (testes/ovaries) originate on the posterior abdominal wall. • They are connected to the anterior abdominal wall (just superolateral to the pubis) by a cord of connective tissue called the Gubernaculum. • This region of the anterior abdominal wall in females becomes the labia majora, • In males, it becomes the scrotum. The gubernaculum guides/ governs the descent of the gonads. • In females, the ovaries remain in the pelvis. • Gubernaculum becomes the proper ovarian ligament and the round ligament of the uterus. • The round ligament of the uterus passes through the inguinal canal and attaches to the labium majus (pl. = labia majora) • In males, the testes pass through the anterior abdominal wall to end in the scrotum. • The gubernaculum becomes the short scrotal/ testicular ligament and the contents of the spermatic cord pass through the inguinal canal. 4 SMU - Internal Data 5 SMU - Internal Data List the coverings of the spermatic cord in relation to the abdominal wall layers. As the spermatic cord traversed the anterior body wall during development, it acquired coverings derived from the layers it came in contact with. Layers of abdomen and corresponding layers in the scrotum: • Peritoneum formed tunica vaginalis testis • On the testis, NOT spermatic cord • Transversalis fascia formed the internal spermatic fascia • Transversus abdominis’ (contributes nothing) • Internal oblique’s lateral fibers and aponeurosis form the cremasteric fascia and cremaster muscle • Innervated by the genital branch of genitofemoral • External oblique’s aponeurosis forms the external spermatic fascia on the surface of the spermatic cord 6 SMU - Internal Data Pneumonic for coverings of spermatic cord: ICE tie Layer Origin Internal spermatic fascia Transversalis fascia Cremasteric muscle and fascia Internal oblique External spermatic fascia External oblique **Reminder that skin of the abdomen contributes to the skin of the scrotum ***Superficial fascia (Camper’s and Scarpa’s fascia) forms dartos muscle and fascia in the scrotum 7 SMU - Internal Data Discuss the difference between indirect inguinal hernias and their relationship to the inferior epigastric vessels and deep inguinal ring. Indirect inguinal hernias • Most common • More common in men than women • Occurs because: • Some or all of the processus vaginalis remains opens or patent • Referred to as being congenital in origin What happens? • Peritoneal sac enters inguinal canal via the deep inguinal ring (lateral to inferior epigastric vessels) • Can traverse entire length of canal, exiting superficial inguinal ring and entering scrotum or labia majus 8 SMU - Internal Data Discuss the difference between direct inguinal hernias and their relationship to the inferior epigastric vessels and deep inguinal ring. Define the boundaries of the inguinal (Hesselbach's) triangle through which direct hernias pass. Direct inguinal hernias • Less common • Commonly seen in mature men • Occurs because: • Weakened posterior abdominal wall • Referred to as being acquired What happens? • Peritoneal sac enters the medial end of the inguinal canal • Bulging occurs medial to the inferior epigastric vessels in the inguinal triangle (Hesselbach’s triangle). Boundaries of triangle: • Laterally inferior epigastric artery • Medially rectus abdominis muscle • Inferior inguinal ligament • Direct inguinal hernia Lateral Medial Does not traverse entire length of inguinal canal but may exit via the superficial inguinal ring Inguinal triangle SMU - Internal Data 9 Pneumonic for hernias: MDs don’t LIe Medial to inferior epigastric vessels=direct hernias Lateral to inferior epigastric vessels=indirect hernias 10 SMU - Internal Data Distinguish inguinal and femoral hernias. Femoral hernia: • More common in females (especially middleaged/elderly) What happens? -Bowel, passes through femoral canal into the medial aspect of the thigh -Function of the femoral canal is to allow expansion of the femoral vein in order to increase venous return. -neck of canal is narrow, prone to trapping bowel and leading to bowel strangulation -Usually acquire, not congenital 11 SMU - Internal Data Define hydrocele, hematocele, and varicocele. Hydrocoele – • a collection of serous fluid within the tunica vaginalis • congenital form is most commonly due to a failure of the processus vaginalis to close. • Adult hydrocele is often associated with inflammation or trauma and rarely, testicular tumors. Hematocoele – • a collection of blood in the tunica vaginalis. • It can be distinguished from a hydrocoele by transillumination (where a light is applied to the testicular swelling). Due to the dense nature of blood, light is unable to pass through. Varicocoele – • gross dilation of the veins draining the testes • The left testicle is more commonly affected, as the left testicular vein is longer and drains into the left renal vein at a perpendicular angle. • A large varicocele can look and feel like a “bag of worms” within the scrotum. 12 SMU - Internal Data