What is the source of pressure pain during abdominal examination in Korean medicine?

BACKGROUND: This study aimed to observe which anatomical structures change in the abdominal cavity and are involved in pressure pain during the pressurization of CV12 by using an ultrasonic diagnostic device in healthy subjects. METHODS: We recruited 52 healthy people and performed ultrasound imaging by gradually pressurizing the subject's CV12. We analyzed ultrasound images to observe the changes in abdominal anatomical structures during pressurization. RESULTS: A significant change in thickness appeared at the space above the peritoneum and stomach and at the space between the stomach and the abdominal aorta while pressing on CV12. Pressure pain occurred in the following two cases. One was when from the posterior side of the stomach to the inner surface of the rectus abdominis became approximately 1.8 cm. The other was when the anterior side of the abdominal aorta approached the inner surface of the rectus abdominis by approximately 3 cm. Pressure pain occurred when CV12 was pressed to a depth of approximately 2.4 cm for females, 3.1 cm for males and 2.7 cm on average. CONCLUSION: The stomach and tissues around the stomach undergo the greatest pressure change during the pressurization of CV12, and in particular, pressure pain occurs when the posterior wall of the stomach is under pressure. However, further study should be done for clinical application.