BL-34 (Xia Liao) Lower Bone Hole

What does BL-34 Xia Liao do?

BL-34 regulates the lower jiao and facilitates urination and defecation, regulates menstruation and stops leucorrhoea, and benefits the lumbar region and legs — and these are WORD FOR WORD the actions our record gives for BL-31.

• Regulates the lower jiao and facilitates urination and defecation
• Regulates menstruation and stops leucorrhoea
• Benefits the lumbar region and legs

The identity is exact, and it is disclosed rather than disguised. Comparing our records directly, BL-31 and BL-34 carry the same three actions in the same order in the same words. That is not an error in either record — it reflects source material that treats the liao points as a functional group rather than as four points with distinct effects. Across seven consecutive scalp points and now four sacral ones, this library’s consistent position is to state such overlap plainly and then name what genuinely differs, rather than inventing a character for each page.

What genuinely differs is the indication list, and the difference is small but real: BL-34 records lower abdominal pain, which BL-31 does not; BL-31 records irregular menstruation and uterine prolapse, which BL-34 does not. Both record low back pain, dysuria, constipation and leucorrhoea.

The eight liao points, verified complete in our own records. Four on each side, over the four posterior sacral foramina — the ba liao, or “eight holes”: BL-31 Shang Liao over the first, BL-32 Ci Liao the second, BL-33 Zhong Liao the third, and BL-34 Xia Liao — this point — the fourth and lowest. Our record also gives BL-34 as a Meeting Point of the Bladder and Gallbladder channels, a designation it shares with BL-31.

Source: Sacred Lotus sources & references (channel, category, action and location records; all four liao points queried and their action and indication records compared word for word against our own data), cross-referenced against multiple online sources.

What is BL-34 Xia Liao used for?

BL-34 is used for low back pain, lower abdominal pain, difficult urination, constipation and abnormal vaginal discharge. Our own indication record is reproduced here in full.

• Low back pain
• Lower abdominal pain
• Dysuria (difficult or painful urination)
• Constipation
• Morbid leucorrhoea (abnormal vaginal discharge)

Four of the five are pelvic, and that is the sacrum’s own anatomy. The nerves supplying the bladder, the rectum and the reproductive organs leave the spinal canal through the sacral foramina — the openings these points sit over. A group of points recorded for urinary, bowel and gynaecological complaints, positioned directly over those openings, is one of the closer correspondences between classical point location and modern anatomy in this library. Stated as a correspondence, not as a mechanism.

An honest note. Lower abdominal pain that is severe, sudden or persistent requires medical assessment — its causes include conditions that are surgical emergencies. Difficulty passing urine, and especially an inability to pass urine, requires urgent assessment. Abnormal vaginal discharge requires assessment rather than repeated self-treatment. Low back pain with leg weakness, saddle numbness or any change in bladder or bowel control is a medical emergency. This record documents classical use and should not delay any of that.

How it is combined. With BL-31, BL-32 and BL-33 — the liao points are used as a group far more often than singly, which is consistent with the identity of their action records. With REN-03 Zhong Ji and REN-04 Guan Yuan on the lower abdomen. With SP-06 San Yin Jiao distally. With BL-35 Hui Yang just below on the coccyx. All held here.

Source: Sacred Lotus sources & references (indication record, compared point by point against BL-31’s; the BL-31 to BL-33, BL-35, REN-03, REN-04 and SP-06 records queried from our own data), cross-referenced against multiple online sources.

Where is BL-34 Xia Liao located?

BL-34 sits over the FOURTH posterior sacral foramen — the lowest of the four holes in the back of the sacrum.

• Over the fourth posterior sacral foramen, the lowest of the set
• BL-33, BL-32 and BL-31 lie above it over the third, second and first foramina
• DU-02 Yao Shu sits below on the midline at the sacral hiatus; BL-35 Hui Yang beside the coccyx

The foramina get smaller going down, and the fourth is the least distinct. That is the practical difficulty with BL-34 specifically: the first and second foramina are usually the easiest to feel, and the fourth is the shallowest and closest to the sacral hiatus below it. A reader locating the set by palpation generally works down from the more definite upper holes rather than up from the bottom.

These points have real holes to find, which is rare on the back. Most trunk points are located by counting spinous processes and measuring outward — a chain in which one miscount displaces everything below. The posterior sacral foramina are palpable openings in bone. That places the liao points in the small group in this library with a genuine bony landmark, alongside DU-02 at the sacral hiatus, ST-02 at the infraorbital foramen and BL-09 at the occipital protuberance.

On the name. “Xia Liao” means Lower Bone Hole. Liao is a hole or crevice in bone, and the four names here are simply upper, second, middle and lower — positional labels within a set rather than descriptions of function. Our BL-05 Wu Chu record notes another counting name of the same kind.

Source: Sacred Lotus sources & references (location and translation records, retained unchanged; the BL-31 to BL-33, BL-35, BL-05, BL-09, DU-02 and ST-02 records queried from our own data).

• A Manual of Acupuncture (p. 295): Over the fourth posterior sacral foramen.
• Chinese Acupuncture and Moxibustion (p. 183): On the sacrum, medial and inferior to Zhongliao (BL-33), just at the fourth posterior sacral foramen.

How is BL-34 Xia Liao needled?

Our own record states perpendicular insertion of 0.8–1.2 inches, with moxibustion applicable — the same range as BL-31, and deeper than most points on the back because the needle is directed toward an opening rather than onto solid bone. What follows is a neutral record of what the reference literature documents. It is not instruction, and this page does not teach technique.

• Angle and depth as recorded: perpendicular, 0.8–1.2 inches — compare 0.3–0.5 inch at the thoracic back points and 0.5–1.0 inch on the lumbar midline.
• Moxibustion: recorded as applicable.
• Regional anatomy: gluteus maximus arises over the lower sacrum; the fourth posterior sacral foramen transmits the posterior ramus of the fourth sacral nerve with accompanying vessels; the sacral canal lies deep, and the pelvic cavity beyond the bone.

Why the depth is greater here. At most back points the vertebral arch or a rib stops the needle. Over a sacral foramen there is an opening in the bone, and the recorded depth reflects that. Our DU-02 record describes the same situation at the sacral hiatus just below this point and draws the same conclusion: where bone does not stop the needle, the recorded depth is doing the work instead.

Hazard, stated proportionately. No pleura, no great vessel at the surface. The structures that matter are the sacral nerve roots passing through and below the foramen and the pelvic contents beyond the sacrum — neither reached by the recorded depth, and both the reason that depth is a range with a stated top.

What is not claimed. No study measuring a safe depth at BL-34 could be located, and none is borrowed. The paediatric CT study this library uses covers 23 points on the trunk and shoulder, from DU-09 upward, and does not reach the sacrum. No case report naming BL-34 was located.

Source: Sacred Lotus sources & references (needling record, retained unchanged, and the recorded depths at the thoracic, lumbar and sacral points compared; the DU-02 record and the point list of PMID 26922245 / PMC4769822 queried from our own data), cross-referenced against multiple online sources; regional anatomy from standard anatomical description.

Is there research on BL-34, and what should a reader know?

No trial isolates BL-34. Where the point appears it is almost always as one of the liao group in a pelvic or obstetric protocol, and a study that includes a point in a protocol is not evidence about that point.

This matters more here than at most points, because the liao points are conventionally needled as a set of four or eight. A trial reporting “BL-34” has in practice almost always treated BL-31 to BL-34 together, which means any effect observed cannot be attributed to the fourth foramen. That is a limitation of the literature rather than a criticism of it, and it is stated so a reader knows what a matching search result actually describes.

What this page can state with confidence. BL-34 sits over the fourth and lowest posterior sacral foramen, completing the ba liao set verified in our own records. Its action record is word for word identical to BL-31’s — three actions, same order, same words — and its indication list differs from BL-31’s in exactly three entries: BL-34 has lower abdominal pain; BL-31 has irregular menstruation and uterine prolapse. That is the whole of the recorded difference between the top and bottom of the set, and stating it precisely is more useful than implying more.

A note on searching for it. “BL 34”, “UB 34” and “Xialiao” searches return protocol trials and unrelated material, and the group-treatment trap above applies to nearly all of them. Our library codes this channel BL- while some sources use UB-. Any claim attached to this point should be checked against what a study actually used.

Source: Sacred Lotus sources & references (location, action and indication records; all four liao points and their action and indication records queried and compared entry by entry against our own data).