Channel Pathways
The Bladder Meridian consists of multiple channel systems, each with its own pathway and clinical significance.
Pathway Description
The external pathway:
- The Bladder Primary Channel starts at Jingming BL-1 at the inner canthus of the eye. It is reached by a branch that separates from Quanliao SI-18 of the Small Intestine Primary Channel. This forms the Hand-Foot second great circuit of Taiyang.
- From BL-1, it ascends the forehead, passing Shenting DU-24, Toulinqi GB-15 and other Bladder Channel points to Baihui DU-20 at the vertex.
- It then descends to Tianzhu BL-10 in the occipital area, where the external pathway splits into two branches:
- The medial branch first travels to Dazhui DU-14 below the 7th spinal process of the cervical vertebra (C7), where it meets the other Yang Primary Channels. From there, the Channel descends parallelly 1.5 cun lateral to the posterior midline.
- At the level of the 2nd lumbar vertebra (L2), one internal sub-branch penetrates deep into the abdomen and connects to the Kidneys and the Bladder.
- The main external medial branch continues descending through the gluteal area and the thigh to Weizhong BL-40 on the popliteal fossa, where it rejoin the lateral branch.
- The lateral branch descends to Fufen BL-41 which is 3 cun lateral to the lower border of the spinous process of the 2nd thoracic vertebra (T2). From there, it continues descending, 3 cun parallel to the posterior midline until reaching Zhibian BL-54 at the level of the fourth sacral foramen. It then runs further down to Huantiao GB-30 at the on the buttock and continues along the posterolateral aspect of the thigh to Weizhong BL-40 to meet the medial branch.
- The medial branch first travels to Dazhui DU-14 below the 7th spinal process of the cervical vertebra (C7), where it meets the other Yang Primary Channels. From there, the Channel descends parallelly 1.5 cun lateral to the posterior midline.
- From Weizhong BL-40, the Primary Channel continues descending along the posterolateral aspect of the foreleg.
- It then reaches Kunlun BL-60 at the lateral malleolus and latterly runs along the lateral border of the foot to Zhiyin BL-67 at the lateral corner of the little toenail. From there, it connects to a branch of the Kidney Primary Channel at Yongquan KID-1 and forms the Foot Yin-Yang second great circuit.
The branches:
- Two branches separates from Baihui Du-20 at the vertex.
- One external branch runs to the tempol and intersects the Gall Bladder Primary Channel at Shuaigu GB-8, Qubin GB-7, Tianchong GB-9, Fubai GB-10, Touqiaoyin GB-11 and Wangu GB-12 along the ear auricle.
- One internal branch enters deep into the brain, meets the Governing Vessel and emerges at Naohu DU-17 above the occipital protuberance, where it rejoins the external pathway.