Lecture Notes - Inguinal Region

The streaming video of the 2004-5 lab overview is available on the web (password protected). The computer presentation used by Dr. Raoof in lecture is available on the web (password protected). You can also download the PowerPoint presentation to print or review.

Descent of Gonads (Ovary & Testis); develop and migrate retroperitoneally:

Gubernaculum: a ligamentous structure that runs between the lower pole of each gonad to each labial/scrotal fold. In the female it becomes the round ligament

Ovary: reaches and remains at the pelvis by the 3rd month.
Definitive ovary: reaches deep pelvis trailing its vessels & nerves.

Testis:

• Processus vaginalis (peritoneal pouch; evaginates into developing scrotum, lies ahead of testis during descent))
• Reaches deep inguinal ring by 7th month;
• Passes through inguinal canal between 7-8 months;
• Reaches scrotum before birth.
• Around birth time: processus vaginalis closes off from peritoneum and forms tunica vaginalis of testis.,

Patent processus vaginalis predisposes to congenital inguinal hernia.

Coverings of the Spermatic Cord:

1. external spermatic fascia: derived from Ext. Oblique fascia
2. cremaster muscle and fascia: derived from Int. oblique muscle and fascia.
3. Internal spermatic fascia: derived from transversalis fascia.

Components of the spermatic cord:

1. ductus deferens
2. testicular artery
3. artery of the ductus deferens
4. pampiniform plexus of veins
5. nerves (autonomic) and lymphatics
6. genital branch of genitofemoral nerve

Inguinal Canal: a diagonal passage formed by the aponeuroses of the three flat abdominal muscles.

Contents of Inguinal Canal

• Spermatic Cord (male) or Round Ligament (female)
• Ilioinguinal Nerve

Boundaries:

1. Superficial inguinal ring: triangular defect in the ext. oblique aponeurosis
2. Deep inguinal ring: in the transversalis fascia.
3. Anterior wall: int.oblique muscle (laterally) and external oblique aponeurosis (medially).
4. Roof: falx inguinalis (arching inferior fibers of internal oblique muscle)
5. Floor: inguinal ligament and lacunar ligament (medially)
6. Posterior wall: transversalis fascia (weak fascia) laterally and conjoint tendon (medially)

Boundaries of Inguinal Triangle (of Hesselbach):

1. Medially: lateral edge of rectus abdominis (linea semilunaris)
2. Laterally: inferior epigastric artery
3. Inferiorly: inguinal ligament

Abdominal Wall Hernias:

1. Inguinal: hernia passes through the inguinal canal for a variable distance and exits through the ext.inguinal ring.
   • Indirect:
     • Congenital; through patent processus vaginalis
     • Acquired: passes through deep inguinal ring initially, i.e lateral to the inferior epigastric artery and exits through the superficial ring.
   • Direct: passes medial to the inferior epigastric artery (in the inguinal triangle) and may pass through the superficial inguinal ring.
2. Femoral: below inguinal ligament.
3. Obturator
4. Other: umbilical; lumbar; incisional; hiatal; etc.

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