ST-33 (Yin Shi) Yin Market

What does ST-33 Yin Shi do?

ST-33 activates the channel, alleviates pain, and dispels wind-damp — a thigh point above the knee, used for the leg it sits on.

• Activates the channel and alleviates pain — the local channel action for the knee and leg
• Dispels wind-damp — wind-damp being the classical cause of the aching, heavy, obstructed bi (painful obstruction) patterns of the joints

A local leg point, honestly. Both recorded actions and every indication concern the knee and leg — ST-33 is a channel point for the lower limb, not a systemic point, and our record does not present it as one. The Stomach channel crosses the front of the thigh here on its way to the knee and shin, and ST-33 is a point on that course, three cun above the kneecap.

“Dispels wind-damp” places it among the joint points. Wind-damp (and wind-cold-damp) obstructing a joint is the classical account of arthritic, achy, weather-sensitive knees — the bi syndromes. A thigh point that dispels wind-damp is aimed at exactly that, and ST-33 sits with the other front-of-knee Stomach points used for the joint.

On the name. “Yin Shi” means Yin Market — yin the yin of yin-yang, shi a market or gathering place. The reading usually offered treats the point as a “market” where yin gathers on the thigh; the name is among the less literal in the system, and our record does not settle its sense.

Source: Sacred Lotus sources & references (channel, action, location and translation records; the surrounding Stomach knee points queried against our own data), cross-referenced against multiple online sources.

What is ST-33 Yin Shi used for?

ST-33 is used for numbness, soreness and impaired movement of the knee and leg, and motor impairment of the lower limbs. Our own indication record is reproduced here in full.

• Numbness of the leg and knee
• Soreness of the leg and knee
• Motor impairment of the leg and knee
• Motor impairment of the lower extremities generally

One region, four ways. Numbness, soreness and impaired movement are the knee-and-leg disorder described from several angles — the whole of the list. ST-33 is a local point for the front of the knee and thigh, used for arthritic knees, weakness and cold-damp leg patterns.

An honest note. New numbness or weakness of a leg requires medical assessment — sudden onset can be neurological and needs same-day care, and persistent numbness can mean nerve compression. A knee that is hot, swollen, locked, or painful after injury requires assessment rather than repeated self-treatment. This record documents classical use only.

How it is combined. With ST-34 Liang Qiu (the Stomach’s Xi-Cleft point, just below it) and ST-35 Du Bi at the knee, and with ST-36 Zu San Li below the knee — the front-of-knee cluster. All held here.

Source: Sacred Lotus sources & references (indication and action records; the ST-34, ST-35 and ST-36 records queried from our own data), cross-referenced against multiple online sources.

Where is ST-33 Yin Shi located?

ST-33 is on the front of the thigh, three cun above the outer top corner of the kneecap, on the line toward the point of the hip.

• 3 cun above the laterosuperior border of the patella (the outer-upper corner of the kneecap)
• On the line joining that corner of the kneecap to the anterior superior iliac spine (the bony prominence at the front of the hip)
• Best found with the knee flexed, which sharpens the kneecap corner as a landmark

Measured up from the kneecap along a defined line. The outer-upper corner of the kneecap and the front point of the hip (the ASIS) are the two ends of the line; ST-33 sits on it, 3 cun above the kneecap. Bending the knee makes the kneecap corner easy to feel. Its lower neighbour ST-34 Liang Qiu sits at 2 cun on the same line.

On the name. “Yin Shi” — Yin Market, as noted above.

Source: Sacred Lotus sources & references (location and translation records, retained unchanged; the ST-34 record queried from our own data).

• A Manual of Acupuncture (p. 155): On the thigh, on a line drawn between the lateral border of the patella and the anterior superior iliac spine, in a depression 3 cun proximal to the superior border of the patella.
• Chinese Acupuncture and Moxibustion (p. 153): When the knee is flexed, the point is 3 cun above the laterosuperior border of the patella, on the line joining the laterosuperior border of the patella and the anterior superior iliac spine.

How is ST-33 Yin Shi 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, into the thigh muscle.
• Moxibustion: recorded as applicable.
• Regional anatomy: the point overlies the rectus femoris and vastus lateralis of the quadriceps on the front-outer thigh; the femoral nerve’s muscular branches and the lateral circumflex femoral vessels run in the region; the femur lies deep.

Hazard, stated proportionately. This is a low-hazard point: no body cavity, no pleura, no organ, thick muscle over bone. Our record carries no arterial caution at ST-33, and it is not among the nine points that do. The thigh tolerates the moderate recorded depth without special concern.

What is not claimed. No study measuring a safe depth at ST-33 could be located, and none is borrowed. No case report naming ST-33 was located.

Source: Sacred Lotus sources & references (needling record, retained unchanged; the nine arterial cautions queried from our own data), cross-referenced against multiple online sources; regional anatomy from standard anatomical description.

Is there research on ST-33, and what should a reader know?

No trial isolates ST-33. Where the point appears it is one component of a knee or leg protocol, and a study that includes a point in a protocol is not evidence about that point.

What this page can state with confidence. ST-33 Yin Shi (“Yin Market”) is a local thigh point for the knee and leg — it activates the channel, alleviates pain and dispels wind-damp, and all its indications concern the lower limb. It sits 3 cun above the outer-upper corner of the kneecap, on the line to the hip, in the front-of-knee Stomach cluster with ST-34, ST-35 and ST-36. It carries no five-shu element and no special classification.

A note on searching for it. “ST 33”, “S 33” and “Yinshi” searches return protocol trials and unrelated material — and “Yinshi” matches Chinese place and personal names. Any claim attached to this point should be checked against what a study actually used.

Source: Sacred Lotus sources & references (action, indication and location records; the front-of-knee Stomach points queried, against our own data).