Which BL point is located 1.5 cun lateral to the lower border of the spinous process of L2?

• A. BL22
• B. BL23
• C. BL24
• D. BL25

Answer: (B)

Back Shu points follow a simple rule: each Zang corresponds to a vertebral level, and the Back Shu point sits 1.5 cun lateral to the lower border of that vertebra’s spinous process. For the Kidney, the related vertebra is L2, so the point located 1.5 cun lateral to the lower border of the L2 spinous process is the Kidney Shu point, BL23. This is how you identify BL23 on the back—find the L2 spinous process, note its lower edge, and measure outward about one and a half finger-widths along the same transverse plane.