BL-55 (He Yang) Yang Union

What does BL-55 He Yang do?

BL-55 activates the channel and alleviates pain, and it stops uterine bleeding and treats pain of the genitals — a gynaecological action on a point in the calf, which is worth stopping on.

• Activates the channel and alleviates pain — the local and channel action
• Stops uterine bleeding and treats pain of the genitals — recorded, and unmatched by anything in the indication list

The mismatch is real, and this library states it rather than reconciling it. Our recorded indications for BL-55 are low back pain and pain and paralysis of the lower extremities — nothing gynaecological at all. The action field and the indication field do not line up. That is the third such mismatch documented in this project, and naming them together makes the pattern visible rather than leaving each looking like an isolated oddity:

• BL-11 Da Zhu — the influential point for the bones, with no bone-disease indication recorded
• BL-51 Huang Men — action benefits the breasts, no breast complaint recorded
• BL-55 He Yang — action stops uterine bleeding, no gynaecological indication recorded

In each case the action field carries a classical attribution that the indication field does not support. A reader working from one field alone would form a different picture than one reading both, which is precisely why both are reproduced on every page in this library.

On the name. “He Yang” means Yang Union. He is to join or unite, and the reading usually offered relates it to the Bladder channel’s branches converging in this region — the channel divides higher on the back and its two lines rejoin near the knee. A positional name describing a channel event rather than an anatomical feature.

Source: Sacred Lotus sources & references (channel, action, indication and translation records, with the action and indication fields compared directly; the BL-11 and BL-51 mismatches queried and confirmed against our own data), cross-referenced against multiple online sources.

What is BL-55 He Yang used for?

BL-55 is used for low back pain, and for pain and paralysis of the lower extremities. Our own indication record is reproduced here in full — two entries.

• Low back pain
• Pain and paralysis of the lower extremities

Both entries are the channel, and neither matches the recorded gynaecological action. As set out above, our action field names uterine bleeding and genital pain and our indication field records neither. Both fields are given here as they stand.

An honest note, and the paralysis entry needs it most. PARALYSIS OR NEW WEAKNESS OF A LIMB IS A MEDICAL EMERGENCY. Sudden weakness — particularly down one side, or in both legs — requires immediate medical care; causes include stroke and spinal-cord compression, where treatment given quickly changes outcomes and delay causes permanent harm. Back pain with leg weakness, saddle numbness or any change in bladder or bowel control is likewise an emergency. This record documents a classical indication in a historical system; it makes no claim that acupuncture treats paralysis, and nothing here should ever delay emergency care.

And on the recorded action, separately: abnormal or heavy uterine bleeding requires medical assessment, and bleeding in pregnancy or after the menopause needs urgent assessment. Genital pain requires assessment. Neither appears in our indication list, but the action field names both, and a reader meeting them there should meet this alongside.

How it is combined. With BL-40 Wei Zhong two cun above, the channel’s He-Sea point and the classical distal point for the back. With BL-56 Cheng Jin and BL-57 Cheng Shan below it in the calf. With BL-23 Shen Shu and BL-25 Da Chang Shu on the low back. All held here.

Source: Sacred Lotus sources & references (indication and action records, compared field against field; the BL-23, BL-25, BL-40, BL-56 and BL-57 records queried from our own data), cross-referenced against multiple online sources.

Where is BL-55 He Yang located?

BL-55 is on the back of the calf, two cun below BL-40, in the hollow between the two heads of the calf muscle.

• 2 cun below BL-40 Wei Zhong, on the line from BL-40 to BL-57 Cheng Shan
• In the depression between the two heads of gastrocnemius — the calf muscle’s inner and outer bellies
• BL-56 Cheng Jin lies 3 cun further down, at 5 cun below BL-40

The calf points are laid out on one line, and our records place them consistently. BL-40 at the knee crease, BL-55 at 2 cun, BL-56 at 5 cun, BL-57 where the two muscle bellies end. Our BL-56 record gives that point both as 5 cun below BL-40 and as midway between BL-55 and BL-57 — and those two descriptions agree only if BL-57 sits 8 cun below BL-40, which is the standard figure for it. Our data does not state that 8 cun directly, so it is offered here as what our two recorded descriptions imply, not as something our record asserts.

The groove between the two heads of gastrocnemius is a real landmark, and it becomes obvious when the calf is contracted — standing on tiptoe, or pointing the foot. That makes this a point located by feel as well as by measurement.

On the name. “He Yang” — Yang Union, the union being the channel’s branches converging in this region.

Source: Sacred Lotus sources & references (location and translation records, retained unchanged; the BL-40, BL-56 and BL-57 positions queried and their recorded distances compared against our own data).

• A Manual of Acupuncture (p. 313): On the lower leg, 2 cun inferior to Weizhong BL-40, on the line connecting Weizhong BL-40 and Chengshan BL-57, in the depression between the two heads of the gastrocnemius muscle.
• Chinese Acupuncture and Moxibustion (p. 188): 2 cun directly below Weizhong (BL-40), between the medial and lateral heads of m. gastrocnemius, on the line joining Weizhong (BL-40) and Chengshan (BL-57).

How is BL-55 He Yang needled?

Our own record states perpendicular insertion of 0.7–1.0 inch, with moxibustion applicable. 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, 0.7–1.0 inch — slightly shallower than the 0.8–1.2 inches our record gives at BL-56 three cun below, where the calf muscle is at its thickest.
• Moxibustion: recorded as applicable.
• Regional anatomy: the two heads of gastrocnemius lie either side, with soleus deeper; the tibial nerve and the popliteal vessels descend between and beneath them, having passed through the popliteal fossa just above; the small saphenous vein runs superficially in the midline of the calf.

Hazard, stated proportionately. No body cavity, no pleura. This is high on the calf, close below the popliteal fossa, where the tibial nerve and popliteal vessels run deep between the muscle heads — and the recorded depth of seven tenths to one inch is what keeps a needle in muscle. Our BL-40 record, two cun above, sits in the fossa proper where those structures are least covered; this point is below that, with muscle in between.

What is not claimed. No study measuring a safe depth at BL-55 could be located, and none is borrowed. Neither measured-depth study this library uses reaches the calf. No case report naming BL-55 was located.

Source: Sacred Lotus sources & references (needling record, retained unchanged, and BL-56's recorded depth compared; the BL-40 record and the point lists of PMID 26922245 and PMID 36075596 queried from our own data), cross-referenced against multiple online sources; regional anatomy from standard anatomical description.

Is there research on BL-55, and what should a reader know?

No trial isolates BL-55. Where the point appears it is one component of a low-back or leg protocol, and a study that includes a point in a protocol is not evidence about that point. It is one of the less-used points on the channel.

The neighbouring point with the literature is BL-40 Wei Zhong, two cun above, among the most-used points on the Bladder channel and present in most low-back protocols. Evidence about BL-40 is evidence about BL-40, and the short distance makes that worth stating — the same caution our BL-38 record gives about the same neighbour from the other side.

What this page can state with confidence, including the discrepancy. BL-55 sits 2 cun below BL-40 between the two heads of the calf muscle, and its recorded indications are two entries, both musculoskeletal. Its recorded action, however, names uterine bleeding and genital pain — and the indication list supports neither. This is the third action/indication mismatch this project has documented, with BL-11 and BL-51, and stating them together is more useful than treating each as a curiosity. Both fields are reproduced here in full so a reader can see the gap rather than inherit whichever one a summary happened to use.

A note on searching for it. “BL 55”, “UB 55” and “Heyang” searches return protocol trials and a large volume of unrelated material — Heyang is a county name and a common element in place and personal names. 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 (action, indication, location and translation records, with the action and indication fields compared; the BL-11, BL-38, BL-40, BL-51, BL-56 and BL-57 records queried and verified against our own data).