DU-09 (Zhi Yang) Extremity of Yang

What does DU-09 Zhi Yang do?

DU-09 sits below the seventh thoracic vertebra, at the level of the diaphragm, and its recorded actions divide cleanly at that line — it treats the chest above and the middle burner below. Our own record holds no five-shu, Yuan or Xi-Cleft classification for it; it is a Governing Vessel point defined by its level on the spine.

• Fortifies the Spleen, drains dampness and regulates the middle burner — the digestive action, from its position at the diaphragm
• Treats jaundice — a specific and unusually persistent classical indication for this point
• Unbinds the chest — the action above the diaphragm, for oppression and cough

Why the T7 level matters. The name “Extremity of Yang” is usually read as marking the point where yang reaches its furthest extent up the back before the upper burner begins. Practically, DU-09 is the Du Mai point at the diaphragm, level with BL-17 Ge Shu (the Back-Shu of the diaphragm and the Hui-Meeting point of Blood) and BL-46 Ge Guan on the outer line — both held here. Points at one spinal level tend to share territory, and that grouping is the clearest way to understand what DU-09 reaches.

Source: Sacred Lotus sources & references (channel, action and location records; the BL-17 and BL-46 levels queried from our own data), cross-referenced against multiple online sources.

What is DU-09 Zhi Yang used for?

Classically DU-09 is used for jaundice, for cough and wheezing, and for stiffness and pain of the back and chest. Our own indication record is reproduced here in full.

• Jaundice
• Cough
• Asthma and wheezing
• Stiffness of the back
• Pain in the chest and back

The jaundice indication is worth pausing on. It is specific, it is old, and it is not obviously derivable from the point’s position — which is a reasonable sign that it comes from observation rather than from theory. A modern reader should treat it as a record of classical use rather than as a claim about liver disease, which is a diagnosis requiring medical assessment.

How it is combined. DU-09 is used with the Back-Shu points at neighbouring levels — BL-17 Ge Shu at the same level, BL-18 Gan Shu (Liver) and BL-19 Dan Shu (Gall Bladder) just below — all three held here. For the chest indications it pairs with the Du Mai points above it, DU-10 Ling Tai, DU-11 Shen Dao and DU-12 Shen Zhu.

Source: Sacred Lotus sources & references (indication record; neighbouring points queried from our own data), cross-referenced against multiple online sources.

Where is DU-09 Zhi Yang located?

DU-09 is on the midline of the back, in the depression below the spinous process of the seventh thoracic vertebra. It is counted from the vertebrae rather than found by a soft-tissue landmark, which is true of every point on this stretch of the Du Mai.

• T7 level — commonly located by dropping to the line joining the lower angles of the shoulder blades, then confirming by counting
• Level with BL-17 Ge Shu, 1.5 cun either side on the inner Bladder line
• Level with BL-46 Ge Guan, 3 cun either side on the outer line

Counting matters here. Miscounting a vertebral level moves the point to a different organ’s territory, and the Du Mai points at T5, T6, T7 and T9 — DU-11, DU-10, DU-09 and DU-08 — are all held in this library and all sit within a few centimetres of each other. There is no palpable feature distinguishing them.

Source: Sacred Lotus sources & references (location record, retained unchanged; sibling levels queried from our own data).

• A Manual of Acupuncture (p. 540): On the midline of the back, in the depression below the spinous process of the seventh thoracic vertebra.
• Chinese Acupuncture and Moxibustion (p. 230): Below the spinous process of the seventh thoracic vertebra, approximately at the level with the inferior angle of the scapula.

How is DU-09 Zhi Yang needled?

The standard texts record oblique insertion directed upward, to roughly 0.5–1.0 inch, with moxibustion applicable. What follows is a neutral record of what the reference literature documents, not instruction for a reader.

• Angle and depth as recorded: oblique, directed superiorly, 0.5–1.0 inch.
• Why obliquely upward: the spinous processes of the thoracic vertebrae slope downward and overlap, so the interspinous space is entered at an angle. The same angle is recorded at the neighbouring thoracic Du points, DU-08 and DU-12.
• Moxibustion: recorded as applicable.

A measurement that describes this point directly. A study of 319 patients aged 4–18 at a single Taiwanese hospital measured safe depth at 23 named points on chest CT, and DU-09 (GV9) is one of them: 27.78 ± 8.88 mm in boys and 24.87 ± 7.83 mm in girls.

Read that figure carefully. For the Governing Vessel points this paper measures skin to the epidural layer, not skin to the pleura as it does for the off-midline points — a distinction the paper makes and one that is easy to miss. The figures are also paediatric, from a single centre, and from patients rather than healthy children; weight was the strongest determinant at all 23 points. A measured distance to a structure is not a recommended needling depth. No adult measurement at DU-09 was located.

Source: Sacred Lotus sources & references (needling record, retained unchanged); measured depth from PMID 26922245 / PMC4769822 (Ma YC et al., BMC Complement Altern Med 2016;16:85), full text read.

What does the name Zhi Yang mean, and is there research on DU-09?

“Zhi Yang” means Extremity of Yang or Reaching Yang. The classical reading places the diaphragm as the boundary between the yang of the upper body and the yin of the lower, making DU-09 the point where yang reaches its limit as it ascends the back. Whether or not one accepts the cosmology, the anatomical observation behind it is sound: T7 is the diaphragmatic level, and the point’s recorded actions split at exactly that line.

Research: no trial isolates DU-09. The point appears in multi-point protocols for back pain and for digestive complaints, and in the classical-prescription data-mining literature, but a study that includes a point in a protocol is not evidence about that point. The one piece of genuinely point-specific data in this record is the anatomical measurement above, and that describes where structures lie — not whether needling helps.

A note on searching for it. Point-code searches for “GV 9” and “Zhiyang” return results that are largely multi-point protocols, and this library has repeatedly found such searches returning material about entirely different subjects — other points, place names, surnames, and in several cases papers that print the wrong point code. Any claim attached to this point should be checked against what a study actually measured.

Source: Sacred Lotus sources & references (name and classification record); PMID 26922245 / PMC4769822 retrieved and read; no retracted sources cited.