Superficial inguinal ring

Location and structure

The superficial inguinal ring is irregularly oval in shape and is located superior to the medial part of the inguinal ligament, above the pubic tubercle (tuberculum pubicum).

It is formed by the divergence of the fibers of the broad flat tendon (aponeurosis) of the external oblique abdominal muscle into two crura:

• Lateral crus (crus laterale) — attaches to the pubic tubercle.
• Medial crus (crus mediale) — attaches to the pubic symphysis.
• Intercrural fibers (fibrae intercrurales) are arcuate fibers that reinforce the lateral part of the ring.

The longitudinal dimension of the opening in men is 2–3 cm, and the transverse dimension is 1–2 cm. In women, these dimensions are half as large.

What passes through the superficial inguinal ring?

The ring is part of the oblique, slit-like inguinal canal (canalis inguinalis). Its contents depend on sex:

• In men — spermic cord (funiculus spermaticus). It includes: ductus deferens (ductus deferens), testicular artery (a. testicularis), pampiniform venous plexus (pampiniformis plexus vv.), cremasteric artery and vein (a./v. cremasterica), artery of the ductus deferens (a. ductus deferentis), lymphatic vessels, genital branch of the genitofemoral nerve (ramus genitalis n. genitofemoralis), sympathetic and parasympathetic fibers, and also the cremaster muscle (m. cremaster).
• In women — round ligament of the uterus (lig. teres uteri) with a neurovascular bundle; the artery of the round ligament of the uterus (a. lig. teretis uteri) passes through the superficial inguinal ring to the corresponding structures.

Note: In the region of the superficial ring, the external spermatic fascia is formed from the aponeurosis of the external oblique abdominal muscle.

Topography and projection onto the internal wall

On the internal surface of the anterior abdominal wall, the superficial inguinal ring corresponds to the medial inguinal fossa (fossa inguinalis medialis).

This paired peritoneal depression lies between the medial umbilical fold (plica umbilicalis medialis) and the lateral umbilical fold (plica umbilicalis lateralis). This fossa is considered a weak point of the abdominal wall.

Clinical significance

• Palpation: This is precisely the area where the physician palpates the superficial inguinal ring during patient examination.
• Herniorrhaphy: When reinforcing the posterior wall of the inguinal canal using Postempski's autoplasty method, the inguinal canal is completely obliterated, and the spermatic cord is relocated into the subcutaneous tissue. A double-breasted aponeurotic flap is created: the lateral flap is sutured over the medial one in an overlapping fashion. When suturing the muscles, it is crucial not to narrow the superficial inguinal ring.
• Cryptorchidism: When testicular descent is impaired, an undescended testis may be located in the region of the superficial inguinal ring. This pathology occurs in 4% of newborn boys and 0.4–0.8% of adults.

Class and exam questions

What else to study on this topic

• Inguinal canal (canalis inguinalis)
• Deep inguinal ring (anulus inguinalis profundus)
• External oblique abdominal muscle (m. obliquus abdominis externus)
• Medial inguinal fossa (fossa inguinalis medialis)

Other topics in the "Anatomical Structures" section

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.