Question

The inguinal ligament (Poupart’s ligament), forming the floor of the inguinal canal, is a modification of the lower border of the aponeurosis of which muscle?

• A. External oblique muscle of the abdomen
• B. Internal oblique muscle of the abdomen
• C. Transversus abdominis muscle
• D. Rectus abdominis muscle

Hint:

The most superficial of the three flat abdominal muscles rolls under to form this ligament.

Answer 1

The Correct Option is A

Step 1: Define the inguinal ligament.
The inguinal (Poupart’s) ligament is a thickened, in-rolled band stretching between the anterior superior iliac spine (ASIS) laterally and the pubic tubercle medially. It forms the floor of the inguinal canal.

Step 2: Identify its origin.
The inguinal ligament is the folded-under (rolled-in) lower free border of the aponeurosis of the external oblique muscle. As the external oblique aponeurosis reaches its lower margin between the ASIS and pubic tubercle, it curves backward and upward on itself to create this ligament.

Step 3: Related derivatives and why other options are wrong.
From the external oblique aponeurosis are also derived the lacunar ligament, pectineal ligament and reflected inguinal ligament. The internal oblique and transversus abdominis form the conjoint tendon (falx inguinalis) and contribute to the roof/cremaster, not the inguinal ligament itself. The rectus abdominis is enclosed in the rectus sheath and does not form this ligament.

Key fact: The inguinal ligament is a modification of the lower border of the external oblique aponeurosis.