Which ligament is most likely lacerated within the inguinal canal after a deep cut 3 cm lateral to the pubic tubercle during parturition (childbirth)?

Round Ligament of the Uterus

The round ligament of the uterus is the structure most likely lacerated within the inguinal canal at this location during parturition. 1

Anatomical Basis

The female inguinal canal primarily contains the round ligament of the uterus as its main structure, analogous to the spermatic cord in males. 1 This ligament:

• Originates at the anterosuperior aspect of the uterus near the tubo-uterine junction 2
• Passes under the broad ligament and traverses the inguinal canal 1, 2
• Crosses through the inguinal canal in more than half of cases (52.6%), with the remainder terminating before the internal inguinal ring (26.3%) or under the pubic bone (22.1%) 2

Location Specificity

A deep cut 3 cm lateral to the pubic tubercle places the injury directly in the path of the inguinal canal where the round ligament courses. 1 The anatomical relationship is critical here:

• The inguinal canal runs obliquely from the deep (internal) inguinal ring to the superficial (external) inguinal ring 3
• The round ligament is the primary structure within this canal in females 1
• This location is too lateral and superficial to involve the rectouterine ligament (which is in the pelvis) 3

Why Other Options Are Incorrect

The ovarian ligament connects the ovary to the uterus entirely within the pelvis and does not traverse the inguinal canal. 3

The suspensory ligament of the ovary (infundibulopelvic ligament) contains the ovarian vessels and remains in the retroperitoneal space, never entering the inguinal canal. 3 While one older study suggested the ligament in the hernia sac might be the suspensory ligament 4, this contradicts established embryological understanding that the gubernaculum persists as the round ligament in females. 3, 1

The mesosalpinx is part of the broad ligament surrounding the fallopian tube and remains entirely within the pelvis. 3

The rectouterine ligament extends from the posterior cervix/uterus to the rectum in the deep pelvis and would not be encountered in an inguinal canal injury. 3

Clinical Context

During parturition, the round ligament can be injured through:

• Direct laceration from episiotomy extension or perineal trauma 3
• Stretching and tearing as it courses through the inguinal canal 3
• The round ligament may also develop varicosities during pregnancy that can complicate the clinical picture 5, 6

Answer: c. Round ligament of the uterus