Jianzhen (SI9): The Back-of-the-Shoulder Point for a Stiff, Aching Shoulder

Where Jianzhen Sits

This point sits at the back of the shoulder, about a thumb's width above the end of the crease at the back of the armpit, in the edge of the large rounded muscle that caps the shoulder.

The line it belongs to begins at the outer corner of the little fingernail. It runs along the little-finger edge of the hand, up the back of the forearm and the back of the upper arm, then zigzags across the shoulder blade before climbing the neck to the face. Vietnamese and Chinese texts call it the Small Intestine channel. This is its ninth stop, and it marks the place where the channel leaves the arm and steps onto the back of the shoulder.

The landmark is the crease at the back of the armpit. When your arm hangs by your side, a fold of skin and muscle runs up from the armpit where the arm meets the back. Its top end is the starting point. The World Health Organization standard of 2008 places the point one unit above that end, and one unit is roughly the width of your own thumb at the knuckle. The Vietnamese handbook by Ngo Trung Trieu describes the same spot as near the lower back edge of the shoulder muscle, one unit straight up from the top of the armpit fold.

Several muscles meet here. The big rounded shoulder muscle (the deltoid) covers it from above. Underneath lies the muscle that runs from the outer edge of the shoulder blade to the arm and helps pull the arm down and back (the teres major), with a smaller partner above it that turns the arm outward (the teres minor). The long head of the muscle at the back of the upper arm (the triceps) runs up between them to the shoulder blade. The axillary nerve, which supplies the shoulder muscle and the skin over it, winds around the back of the arm bone close to this spot. That is why a firm press here can send a dull ache across the back of the shoulder.

Why This Spot

On the anatomical side, this is a crossroads. The small muscles that hold the ball of the shoulder in its socket meet the large muscles that lift and lower the arm, all within a few finger-widths. When a shoulder stiffens, these muscles guard the joint, and the guarding often settles right here. People who reach overhead, carry bags on one side, or have stiffened after a fall or a period of rest often find this spot sore to touch.

In this tradition the point is described as the doorway where the channel enters the shoulder proper. Its name says so plainly: this is the true shoulder, the place where the arm becomes the shoulder. The Vietnamese name, Kiên Trinh, carries the same meaning. Teachers use it when the shoulder joint aches deep inside, when the arm will not lift to comb the hair, or when pain runs down the back of the upper arm.

What the Old Texts Say About Jianzhen

The Plain Questions, the Suwen, a Han-dynasty text that is one half of the Yellow Emperor's Inner Classic, already mentions this point by name, in its chapter on the residences of qi, among the holes of the hand channels around the shoulder. Its name has stayed the same for roughly two thousand years. That steady naming tells you the old writers saw this spot as part of the core set for the shoulder, not a later addition.

The Vietnamese handbook of points and channels by Ngo Trung Trieu, published by Hong Duc, lists it for pain around the shoulder joint and the soft tissues around it, and for pain of the upper arm. It also lists heavy sweating in the armpit. Most of those entries stay close to the point itself. That is typical of points near a joint: they are used, above all, for the joint they sit beside.

The WHO standard of 2008 placed it in plain terms: below and behind the shoulder joint, one unit above the end of the back armpit crease. That clear landmark makes it easy to find on yourself, even through a little extra padding, because the armpit crease does not move.

In the wider tradition, teachers pair it with a point at the front of the shoulder and a point at the back of the shoulder tip, so that the joint is worked from three sides. That habit comes from long practice rather than proof. It reflects a plain idea that still makes sense: a stiff shoulder is stiff all the way around.

Points That Work With Jianzhen

The first partner sits in the middle of the shoulder blade, in a soft hollow about a third of the way down from the bony ridge that crosses the top of the blade. It is the second dot in the photo. In this tradition the two are commonly pressed one after the other when the back of the shoulder aches and the ache spreads across the blade.

The second sits at the front of the shoulder. Raise the arm out to the side to shoulder height and two dips appear at the bony tip of the shoulder. The point is in the front dip. It is used with this one to work the joint from front and back.

The third is in the back dip at the shoulder tip, the partner of the front one. With the arm raised to the side, feel for the hollow behind the bony tip. Together the three surround the joint, and many people press all three in the same sitting.

How to Find and Press Jianzhen

Getting Into Position

This point is awkward to reach with your own fingers, and twisting a sore shoulder to get there makes things worse. Use a ball or a tool instead. For a ball, stand with your back to a wall, turned slightly so the sore shoulder is nearest the wall, and place a firm ball, such as a tennis ball, between the wall and the back of the shoulder, behind the armpit. For a tool, sit upright and hook a long-handled pressing tool, the hooked or S-shaped kind, over the opposite shoulder and down the back. Let the arm on the sore side hang loose against your body.

How to Find It

Before you press, find the landmark with your free hand. Let the arm on the sore side hang. Reach across your chest with the other hand, under the armpit, and feel the thick fold at the back of the armpit where the arm joins the back. Follow that fold up until it ends against the shoulder. From that end, go about one thumb's width straight up. That is the area.

Now probe the area with the tool's rounded tip, or with the ball by bending your knees and shifting your body in small steps. Most of it will feel like firm muscle. One spot will sting: a small, sharp, pinpoint tenderness. That spot is the point. If you feel tingling or a jolt down the arm, you are too low and too deep, near the nerves that pass under the armpit. Move up a little and press more lightly.

How to Press It

Keep the tip or the ball on the stinging spot and rub in small circles, about the size of a fingernail, roughly one each second. With a tool, make the pressure by pulling the handle with your front hand; do not tense the sore shoulder. With a ball, make the circles by shifting your weight in small movements. Aim the pressure inward, toward the centre of the shoulder joint. Keep the tip on the same spot; do not let it roll over the whole shoulder.

How Much Pressure

A sharp sting under the tip is right. That small sting tells you that you are on the point. The test is what happens when you lift off: the sting should fade within moments. If the pain stays after you lift off, if it spreads, or if the area turns swollen, hot or red, stop and leave it for several days. If you are holding your breath or your shoulder creeps toward your ear, you are pressing too hard. Step closer to the wall, or loosen your pull on the tool, until you can breathe slowly through the sting.

How Long

Work each shoulder for one to three minutes. Keep the first sessions to about one minute, because a stiff shoulder is often tender here. As the days go on, add a little time, up to three minutes. Do both sides, even when only one complains, because the good shoulder has usually been doing extra work. Once or twice a day is plenty. Pressing longer adds soreness, not benefit.

When to Do It

Morning suits a shoulder that is stiff on waking, once you have warmed up with a few gentle movements. Late afternoon suits the ache that builds after reaching, lifting or carrying. Before bed is a good time too, as part of winding down, especially if lying on that side is uncomfortable. Do not press in the middle of the night. If an aching shoulder wakes you, pressing then tends to wake you further. Keep the pressing for the day and the evening, and try a pillow under the arm to rest the shoulder.

What This Won't Do

It will not loosen a joint that has stiffened from the inside, and it will not rebuild a worn joint or a torn tendon. Shoulder pain in later life often comes from wear in the tendons that cap the joint, from a frozen shoulder, from arthritis, or from a neck that sends pain into the shoulder. A point at the back of the shoulder cannot out-argue any of that. Pressing works best alongside the plain things: gentle daily movement within comfort, exercises from a physiotherapist, and not sleeping on the sore side.

It will not replace a diagnosis either. A shoulder that suddenly will not lift after a fall needs to be seen, because a tendon can tear or a bone can crack. A shoulder that is hot, red and swollen, especially with a fever, needs urgent attention. Pain at the top of the shoulder that comes with breathlessness, sweating, or pain in the chest or jaw needs emergency care, not pressing. Numbness or weakness in the arm or hand points to the neck and should be checked. Pain that keeps you awake every night or worsens week on week belongs with a doctor.

Safety First

Do not press over skin that is broken, burned, infected, badly bruised or rashy. Leave the area alone after a recent shoulder injury, dislocation or surgery, and ask your surgeon when you may start. Avoid any lump or swelling in or near the armpit, and have it checked. If you have osteoporosis, take blood thinners or bruise easily, use lighter pressure, keep sessions short, and talk to your doctor first.

Stop at once if the pain stays after you lift off, spreads, or if the area becomes swollen, hot or red. Stop too for any electric jolt, tingling or numbness down the arm. Nothing here requires you to push through pain. For the full list of cautions, read the full safety guide before you begin.

Questions People Ask

Where is the Jianzhen (SI9) pressure point? Jianzhen (SI9) sits at the back of your shoulder. Let your arm hang and find the crease at the back of the armpit. Follow it up to its top end, then go one thumb's width straight up. The point is in the edge of the shoulder muscle there. In English it is called the True Shoulder; in Vietnamese, Kiên Trinh.

The photo shows two red dots. Which one is Jianzhen? The dot at the outer edge of the back, near the armpit, is Jianzhen (SI9). The dot in the middle of the shoulder blade is Tianzong (SI11), a nearby point shown to help you get your bearings. The two are often pressed one after the other.

How do I reach Jianzhen on myself? The easiest way is a firm ball, such as a tennis ball, placed between the back of your shoulder and a wall. Stand slightly turned so the ball sits behind the armpit and lean into it. A long-handled pressing tool, the hooked or S-shaped kind, also works if you hook it over the opposite shoulder and down the back.

How long should I press Jianzhen? One to three minutes on each side. Start with about a minute, then add a little time over the days, up to three. Once or twice a day is enough. Work both shoulders, even if only one aches.

Can I press Jianzhen with a frozen shoulder? In this tradition the point is commonly used for a shoulder that will not lift or turn. Press gently and stay within comfort; forcing the joint does not help. A frozen shoulder needs a proper diagnosis and usually gentle exercises from a physiotherapist, and pressing works best alongside that.

I feel tingling into my hand when I press. What does that mean? Stop and lift off. Large nerves to the arm pass under the armpit, and pressing too low or too deep can reach them. Move the tip a little higher, toward the shoulder, and press more lightly. The sensation you want is a small sting under the tip, nothing that travels down the arm.

Other Points in This Library

Each of these sits within reach of the same hand. They are often worked in the same sitting.

This page shares general information about a traditional practice. It is not medical advice and does not replace what your doctor has given you. If you are pregnant, managing a health condition, or unsure whether this applies to you, check with your doctor first.

The whole inner edge of the foot, laid out on one page with photographs, is in The Foot Map — the free book. For every point in this library, see the full pressure point index.

(Point shown: SI9 · Jianzhen · True Shoulder · Kiên Trinh.)