The ?? in the following diagram is an important bony landmark used to differentiate between inguinal and femoral hernias. It is? (See Figure)

Ans. C. Pubic tuberclePhysical Examinationa. Physical examination is the best way to determine the presence or absence of an inguinal hernia. The diagnosis may be obvious by simple inspection when a visible bulge is present. The differential diagnosis must be considered in questionable cases (Table 36-4). Nonvisible hernias require digital examination of the inguinal canal. This is best done in both the lying and standing position. The examiner should place the tip of the index finger at the most dependent part of the scrotum and direct it into the external inguinal ring. The patient is then asked to strain. The ritual of having the patient cough is discouraged as it results in the over diagnosis of a hernia because of the difficulty of differentiating a normal expansile bulge of muscle from a true hernia, especially in asthenic individuals.b. Numerous authors have shown that the accuracy with which direct and indirect inguinal hernias can be distinguished clinically before surgery is low. 28,29,30 However, classic teaching is that an indirect hernia will push against the fingertip, whereas a direct hernia will push against the pulp of the finger. In addition, applying pressure over the mid- inguinal point (midway between the anterior superior iliac spine and the pubic tubercle, and just above the inguinal ligament) with the fingertip will control an indirect hernia and prevent it from protruding when the patient strains. A direct hernia will not be affected with this maneuver.c. A femoral hernia presents as a swelling below the inguinal ligament and just lateral to the pubic tubercle. Femoral hernias are over diagnosed because of the presence of a prominent femoral fat pad, a so-called femoral pseudohernia. Thin patients commonly have prominent bilateral bulges below the inguinal ligament medial to the femoral vessels. They are asymptomatic and disappear spontaneously when the patient assumes a supine position. Surgery is not indicated.