Inguinal canal & hernia landmarks
What it means
The deep (internal) inguinal ring lies LATERAL to the inferior epigastric vessels. An INDIRECT hernia enters through it, so the inferior epigastric vessels lie immediately MEDIAL to the neck of an indirect sac. A DIRECT hernia pushes through Hesselbach's triangle — MEDIAL to the vessels (boundaries: inferior epigastric vessels laterally, lateral border of rectus medially, inguinal ligament inferiorly). Canal contents: spermatic cord (M) / round ligament (F) + ilioinguinal nerve.
Worked example
"What lies immediately medial to the neck of an indirect inguinal hernia sac?" → the inferior epigastric vessels — the landmark separating indirect (lateral) from direct (medial).
In the exam
A male infant has an indirect inguinal hernia; the structure lying immediately medial to the neck of the sac is identified at operation.
What settles it
Indirect = LATERAL to the inferior epigastric vessels (through the deep ring, can reach the scrotum); direct = MEDIAL to them (through Hesselbach's triangle).
Source: TeachMeAnatomy — Inguinal canal