Understanding Surface Anatomy: Key Landmarks of the Abdomen
School
Trinity International University**We aren't endorsed by this school
Course
AEROSPC 1
Subject
Anatomy
Date
Dec 9, 2024
Pages
2
Uploaded by lesong8374
Surface anatomy * Defining the surface projection of the abdomen Defining the surface projection of the abdomen Palpable landmarks can be used to delineate the extent of the abdomen on the surface of the body. These landmarks are: u the costal margin above; and m the pubic tubercle, anterior superior iliac spine, and iliac crest below (Fig. 4.161). The costal margin is readily palpable and separates the abdominal wall from the thoracic wall. A line between the anterior superior iliac spine and the pubic tubercle marks the position of the inguinal ligament, which separates the anterior abdominal wall above from the thigh of the lower limb below. The iliac crest separates the posterolateral abdominal wall from the gluteal region of the lower limb. The upper part of the abdominal cavity projects above the costal margin to the diaphragm and therefore abdomi- nal viscera in this region of the abdomen are protected by the thoracic wall. The level of the diaphragm varies during the breathing cycle. The dome of the diaphragm on the right can reach as high as the fourth costal cartilage during forced expiration. Costal margin lliac crest Anterior superior iliac spine Inguinal ligament Pubic tubercle Thorax Abdomen —-:——— Lower limb Fig. 4.161 Interior view of the abdominal region of a man. Palpable bony landmarks, the inguinal ligament, and the position of the diaphragm are indicated.
384 Abdomen How to find the superficial inguinal ring The superficial inguinal ring is an elongate triangular defect in the aponeurosis of the external oblique (Fig. 4.162). It lies in the lower medial aspect of the anterior abdominal wall and is the external opening of the inguinal Anterior superior iliac spine \ /_,, . Inguinal ligament Femoral artery Spermatic cord Anterior superior iliac spine / Inguinal ligament ———-—Jx————-— // Femoral artery Round ligament of uterus c / T canal. The inguinal canal and superficial ring are larger in men than in women: ® in men, structures that pass between the abdomen and the testis pass through the inguinal canal and superfi- cial inguinal ring; Aponeurosis of external oblique & Deep inguinal ring Superficial inguinal ring Position of pubic symphysis = Aponeurosis of external oblique = ——— Deep inguinal ring Superficial inguinal ring = Position of pubic symphysis Fig. 4162 Groin. A. In a man. B. In a woman. C. Examination of the superficial inguinal ring and related regions of the inguinal canal in a man.