Lecture Notes - Inguinal Region

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.