Yinlingquan (SP9): The Inner Knee Point for Knee Pain and Puffy Legs

Where Yinlingquan Sits

This point sits on the inner side of the leg, in the dip under the bony flare of the shinbone below the knee, thirteen proportional units above the inner ankle bone.

The line this point belongs to starts at the inner corner of the big toenail. It runs along the inner edge of the foot, passes in front of the inner ankle bone and climbs the inner side of the shin, close behind the bone. It crosses the inner knee, runs up the inner thigh and the front of the belly, and ends on the side of the chest. Vietnamese and Chinese texts call it the Spleen channel. This is its ninth stop, and the last one below the knee.

The old texts place it on the inner side of the leg, in the dip between the lower edge of the inner flare of the shinbone and the shin's inner border. The shinbone widens near the top, like the base of a column, to carry the knee. On the inner side that widening is the medial condyle. Where the straight inner edge of the shin meets the underside of that flare, there is a corner, and the point sits in it. Here, too, the bone is the landmark. No measuring is needed.

Underneath, several things pass close together. The tendons of three thigh muscles fan out over the upper inner shin a little in front of the point, where they anchor to the bone (the pes anserinus). Behind it lies the inner head of the calf muscle. The point sits in the soft gap between these, against the bone.

The skin here is served by the saphenous nerve, a long branch of the nerve that runs down the front of the thigh, carrying fibres from the third and fourth lumbar roots. Those roots also serve the front of the thigh and the inner side of the knee and shin. A large surface vein, the great saphenous vein, runs up the inner side of the leg close behind the point. That is why you should look and feel before you press, and move off any vein that bulges.

Why This Spot

From the anatomical side, the point is easy to find because the bone does the finding for you. Slide a thumb up the inner edge of the shin and the bone stops it. The corner is the same on every leg, large or small, and it can be reached from a chair. The inner knee is also a common place for pain in people in their sixties and seventies. Wear on the inner side of the joint, and irritation of the tendons that anchor there, both show up as tenderness close to this spot.

In this tradition the point is the sea point of its channel, where the flow is described as running deepest, like a river reaching the sea. The channel itself is linked with the way the body handles fluid and dampness. The old books describe this point as one that moves water downward and out. That is why it is reached for when the legs feel heavy and puffy, or when urine is slow to come. It is a traditional idea, not a medical one, but it has shaped how the point has been used for centuries.

The name mirrors its partner on the outer side of the knee. The inner side of the body is the yin side; the bony flare is the mound; the dip under it is the spring. Its Vietnamese name, Âm Lăng Tuyền, carries the same picture.

What the Old Texts Say About Yinlingquan

The point holds a special place in the measuring system for the leg. The proportional units used to place points on the lower leg are recorded in the Lingshu, the Spiritual Pivot, a Han-dynasty text. The World Health Organization's 2008 standard still rests on them, and it uses this very point as a marker. From this corner under the knee down to the inner ankle bone is counted as thirteen equal units. Several points on the inner shin are measured from here, including the one four fingers above the inner ankle.

The Vietnamese handbook of points and channels by Ngo Trung Trieu, published by Hong Duc, lists it for knee pain and swelling of the knee joint, for irregular periods, for bowel complaints, for a swollen belly, and for urine that will not flow or that leaks. Most of those entries share one theme: fluid that is not moving the way it should. That matches the traditional reasoning described above.

The same handbook gives a precise finding method. Look for the dip behind the inner edge of the top of the shinbone, level with the most raised point of the bony bump at the front of the shin below the kneecap. In plain terms: find the bump on the front of the shin below the kneecap, run a line straight across to the inner side at that level, and the dip on that line, against the bone, is the point.

In the wider tradition, this point and its outer twin are taught together. Teachers often have students find both in the same sitting, thumb inside and fingers outside, because the two mounds and two springs make the knee easy to map. Nothing about that proves what the points do. It tells you that ordinary people have used this pair for knee complaints for a very long time.

Points That Work With Yinlingquan

The first partner sits above the knee on the same side. Sit with the knee bent and place your palm over the kneecap, fingers pointing up the thigh. On the inner side, about three finger-widths above the top of the kneecap, there is a bulge of thigh muscle; the point sits on it. It is commonly paired with this one for an aching inner knee.

The second is lower on the same line. Find the tip of the inner ankle bone, lay four fingers above it, and probe the soft edge right behind the shinbone. It is used with this one for heavy, puffy lower legs. That ankle point carries a caution in pregnancy, so leave it alone if that applies to you.

The third sits on the outer side of the same knee, almost exactly opposite. Find the small round bony knob on the outer leg below the knee and slide into the dip in front of and below it. The two are often held together, thumb on the inside and fingers on the outside, for a knee that aches right across.

How to Find and Press Yinlingquan

Getting Into Position

Sit on a firm chair with your feet flat and your knee bent to roughly a right angle. Let the knee fall a little outward, so the inner side of the leg turns toward your hand. Do not tense the calf. If that is awkward, sit on a bed with the leg bent and resting on its outer side on a pillow.

How to Find It

Place your thumb on the inner edge of the shinbone, about halfway down the leg. You will feel the hard, flat face of the bone in front and the softer calf muscle behind. Keep the thumb on that edge and slide it slowly up toward the knee. A hand's width below the knee the bone starts to widen. Then it flares out sharply and stops the thumb. The corner under that flare is the area.

Look before you press. If a large blue vein runs over the spot, or you feel a soft rope-like bulge, move a little forward toward the bone. Now probe the corner with a rounded-tip pressing tool, or the tip of your thumb with the nail cut short, moving slowly in small steps. Most of it will feel like ordinary tissue, perhaps achy. One spot will sting: a small, sharp, pinpoint tenderness. That spot is the point. On a sore knee it is often very easy to find.

How to Press It

Keep the tip of the tool or thumb on the stinging spot and rub in small circles, about the size of a fingernail, roughly one each second. Aim the pressure in toward the bone and slightly upward, under the flare, not downward into the calf. Rest the outer side of the knee in your other hand, or against the chair, so the leg stays still. Keep the tip on the same spot; do not let it skate over the skin.

How Much Pressure

Sharp under the tool is right. That small sting means you are on the point. The test comes when you lift off: the sting should fade within moments. If the pain stays after you lift the tool, if it spreads, or if the area turns swollen, hot or red, stop and leave it for several days. Stop also for any electric or numb feeling running down the shin. If you are holding your breath or gripping the chair, you are pressing harder than you need to. Ease off until you can breathe slowly through the sting.

How Long

Work each leg for one to three minutes. In the first sessions, stay near one minute, because the point is often very tender at the start, especially on a sore knee. As the days go on, add a little time, up to three minutes. Do both legs, even when only one knee aches. Once or twice a day is plenty. Pressing longer does not help more; it mostly adds soreness.

When to Do It

Morning suits a knee that is stiff and slow on waking. Late afternoon suits lower legs that have grown heavy and puffy after a day on your feet; raising the legs for a while afterwards makes sense too. Before bed is a good time as part of winding down. Do not press in the middle of the night. Many people in their sixties are woken by the bladder or by an aching knee, and pressing then tends to wake you further. Keep the work for the day and the evening.

What This Won't Do

It will not remove the reason your knee aches or your legs swell. With the inner knee, the reason is often wear in the joint, weak thigh muscles, extra weight or years of loading the joint in one way. Puffy legs often come from long hours sitting or standing, from heat, from some medicines, or from veins that no longer return blood well. A dip under your knee will not out-argue any of that. Pressing works best alongside gentle strengthening, walking, raising the legs, and the support stockings or footwear your doctor suggests.

It will not replace a diagnosis either. Swelling in one leg only that is sudden, warm and painful needs urgent assessment, because it can mean a clot in a deep vein. Swelling in both legs that comes with breathlessness, a cough when lying flat or rapid weight gain needs to be seen soon. A knee that is suddenly hot, red and swollen, especially with fever, needs a doctor that day. Pain or burning when passing water, blood in the urine, or being unable to pass water at all are also for a doctor, not a thumb. Time spent pressing is time not spent getting those looked at.

Safety First

Do not press over skin that is broken, burned, infected, badly bruised or rashy. Never press on a bulging vein; if you have varicose veins on the inner leg, or have had a clot in that leg, ask your doctor before working this point. Skip it if the knee is hot and swollen or you had knee surgery recently. Leave the area alone with a recent fracture, a fresh sprain, unexplained swelling, or a plate, pin or implant under the skin. If you take blood thinners, bruise easily, or have reduced feeling in your legs, 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 or numb sensation. Nothing here asks you to push through pain. For the full list of cautions and the situations where pressing on yourself is not appropriate, read the full safety guide before you begin.

Questions People Ask

Where is the Yinlingquan (SP9) pressure point? Yinlingquan (SP9) sits on the inner side of your leg, right below the knee. Put your thumb on the inner edge of the shinbone and slide it up toward the knee. Where the bone flares out and stops the thumb, there is a dip. Probe that dip until one spot stings. In English it is called the Spring by the Inner Mound; in Vietnamese, Âm Lăng Tuyền.

How long should I press Yinlingquan? One to three minutes on each leg. Keep the first sessions to about a minute, then add a little as the days go on, up to three. Once or twice a day is enough. Work both legs, even when only one knee aches.

There is a vein running near the spot. Is that a problem? A large vein runs up the inner side of the leg close to this point. If you can see or feel a bulging, rope-like vein right on the spot, do not press on it. Shift a little forward toward the bone, or skip the point. If you have varicose veins or have had a clot in that leg, ask your doctor first.

Can I press this point for puffy ankles? In this tradition it is commonly used for heavy, puffy lower legs. But swelling has many causes, and some of them need a doctor. If the swelling is new, in one leg only, or comes with breathlessness, get it checked before you press anything.

Is it the same as the point on the outer side of the knee? No. The outer point sits in front of the small bony knob on the outside of the leg, almost exactly opposite this one. The two are old partners. You can work one after the other, or hold both at once with your thumb on the inside and your fingers on the outside.

Can I press it at night when I wake up to pass water? It is better not to. Pressing in the middle of the night tends to wake you further. Do your sessions in the daytime or as part of winding down before bed, and mention frequent night trips to the toilet to your doctor.

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: SP9 · Yinlingquan · Spring by the Inner Mound · Âm Lăng Tuyền.)