The abdominal examination is completed by exposure and full examination of the inguinal regions – the scrotum and penis in the male and the vulva in the female. Although the anterior superior iliac spines are palpable, the pubic tubercles and symphysis pubis may be difficult to palpate in obese subjects.
The inguinal ligament extends from the anterior superior iliac spine to the pubic tubercle (figure 53). Direct and indirect inguinal hernias extrude through the superficial inguinal ring, above and medial to the pubic tubercle. Inguinal hernias often reduce spontaneously in the supine position, but usually reappear on asking the patient to cough or stand.
Place your middle and ring fingers over the superficial inguinal ring and ask the patient to cough (figure 54a–c). If a hernia is present, the gut can be felt to extrude through the ring. This has to be differentiated from tensing of the abdominal wall and the slight bulging of the suprainguinal region just lateral to the tubercle, often present in normal individuals and termed a Malgaigne’s bulge. Both inguinal regions must be examined, even if a patient is complaining of just a unilateral lump, since the condition is often bilateral.
Figure 53 Anatomy of inguinal region
1. Aortic bifurcation
2. Right common iliac artery
3. Left internal iliac artery
4. Left external iliac artery
5. Midinguinal point
6. Iliopsoas muscle
7. Right common femoral artery
8. Pectineus muscle
9. Sartorius muscle
10. Left profunda femoris artery
11. Left superficial femoral artery
12. Adductor longus muscle
If a hernia is not obvious, ask the patient to stand up and cough again. If there is still doubt, ask the subject to don some clothes, and walk and climb some stairs, but on return to remain standing until examined in this position again (figure 55).
In the male it is possible to invaginate the upper part of the scrotum superiorly subcutaneously into the superficial inguinal ring, even in an obese patient, and for the cough impulse of a hernial sac to be felt (figure 56). This maneuver, however, must be undertaken very gently, as it may cause discomfort, and the invagination of the scrotum must start low enough to follow the line of the spermatic cord, deep to subcutaneous fat.
Once a hernia has been found it is important to be sure that it is reducible and, once reduced, to differentiate between a direct and an indirect inguinal hernia, by seeing if the cough impulse can be controlled by pressure over the deep inguinal ring. Whether you test this in the lying or standing position depends on the ease of reducing and reproducing the hernia by coughing. The deep inguinal ring is situated just above the midpoint of the inguinal ligament. Place your finger over this site after hernia reduction, and ask the subject to cough, either in the standing or lying position, depending on how the hernia is most easily reproduced.
A number of structures produce masses below the inguinal ligament. Common findings are inguinal lymph nodes and femoral hernias. The latter appear below and lateral to the pubic tubercle; they are usually more difficult to reduce than their inguinal counterparts. A tender, irreducible hernia is difficult to differentiate from a tender lymph node in this region. Other lumps in this region include a saphenous varix, a femoral aneurysm, abscesses, from degenerate lymph nodes or the extension of a psoas abscess, and a psoas bursa.