Discussion on the Route of Lung Meridian: Focus on LU3 and LU4

Abstract

Objectives : An error was found in the recent standard by the World Health Organization (WHO) on the locations of the Upper arm Route of Lung Meridian (URLM) and its acupoints LU3 and LU4. This possible incorrect information is being taught throughout Korean medicine colleges nationwide, which follow WHO standards. Therefore, an investigation is required to sort out this discrepancy based on the evidence in historical documents. Methods : The location of WHO's URLM and LU3 and LU4 were compared with corresponding information in the classical literature. The anatomical structure mentioned in these classical documents was examined. Finally, an assessment was conducted on whether this structure is reflected in the WHO standards. Results : Classical literature prior to the early 20th century records the locations of the Lung Meridian and LU3 and LU4 of the upper arm to be in the artery on the medial aspect. This artery corresponds to the brachial artery. The location established by the WHO is on the anterolateral side of the upper arm, where no large arteries exist that can be found by haptic search or angiographically. The anterolateral side of the upper arm belongs to the Yang aspect, which does not coincide with the Yin aspect of Lung Meridian. Conclusions : The WHO's URLM and LU3-4 standards do not agree with the classical literature. The correct route must coincide with the brachial artery passing through the medial side of the humerus. The actual location of LU3-4 is on the medial aspect of the arm, just medial to the border of the biceps brachii muscle, on the brachial artery, 3-4 B-cun inferior to the anterior axillary fold.