Yingu (KI10): The Inner Back-of-Knee Point for a Stiff, Aching Knee

Where Yingu Sits

This point sits at the inner end of the crease behind the knee, in the groove between two tendons that stand out when the knee is bent.

The line this point belongs to begins on the sole of the foot, circles behind the inner ankle bone, and climbs the inner side of the leg. It passes the back of the inner knee here, continues up the inner thigh, and runs up the front of the body beside the midline to the collarbone. Vietnamese and Chinese texts call it the Kidney channel. This is its tenth stop, and the last one on the leg below the thigh.

The old texts place it behind the inner bulge at the top of the shinbone, below the large tendon and above the small one. The Vietnamese handbook makes it clearer: at the inner end of the back-of-knee crease, behind the inner bump of the shinbone, in the gap between two tendons. The lower tendon is thin and firm. The upper one is broader and softer. Bend the knee and both stand out under the skin.

Underneath, the two tendons belong to two of the hamstring muscles on the inner back of the thigh. The thin, cord-like one is the semitendinosus. The broader, flatter one is the semimembranosus. Both bend the knee and pull the leg back at the hip, and both attach to the inner side of the top of the shinbone. The point sits in the narrow valley between them, right where they cross the knee crease.

The nerves here explain why the area is sensitive. The skin is served by branches from the back and inner thigh, and the hamstrings beneath are supplied by the tibial part of the large nerve that runs down the back of the thigh, from the low lumbar and upper sacral roots. In the middle of the back of the knee, away from this point, a large artery and vein pass through. That is why this page keeps to the inner end of the crease.

Why This Spot

On the anatomical side, the inner back of the knee is where the inner hamstrings cross the joint. When a knee is stiff and will not straighten fully, these tendons stay short and tight. People with worn knees often feel a pulling ache here when they stand up or try to straighten the leg. The groove between the tendons is easy to find once the knee is bent, and it is soft enough to press without strain.

In this tradition the point is described as the sea point of its channel, where the flow is said to run deep and gather, like a river entering the sea. Sea points near the knee and elbow are often used for the joints they sit beside and for complaints further along the channel. This line runs up the inner thigh, so the point is also pressed when the inner knee and the inner thigh ache together.

The name describes the place. The inner side of the leg is the yin side, and the groove between the tendons is the valley. The Vietnamese name, Âm Cốc, means the same: the valley on the yin side.

What the Old Texts Say About Yingu

The Lingshu, the Spiritual Pivot, a Han-dynasty text, lists the key points of each channel near the elbows and knees. It names this point as the sea point of the Kidney channel, placed behind the inner bump of the shinbone, below the large tendon and above the small one, felt with the knee bent. That description has been repeated in nearly every handbook since. The World Health Organization's 2008 standard keeps it in modern words: on the back of the knee, slightly toward the inner side, at the inner end of the knee crease, beside the semitendinosus tendon.

The Vietnamese handbook of points and channels by Ngo Trung Trieu, published by Hong Duc, describes its uses in the language of the tradition: drawing out dampness, easing the passing of water, nourishing the kidney, clearing heat, and freeing the lower part of the body. These are traditional ideas, not medical findings. In everyday practice they translate into the point being used for an aching inner knee and inner thigh, and for a heavy, damp feeling in the lower body.

The handbook's way of finding it matches this page. Bend the knee so the tendons stand out, find the inner end of the back-of-knee crease, and feel for the gap between the thin, firm tendon below and the softer, larger one above.

In the wider tradition the point is often worked with its neighbour a finger's width in front of it, which belongs to a different line. Between them they cover the inner end of the crease, a spot that aches in many people whose knees are stiff. Long use rather than trials stands behind this, as with most points.

Points That Work With Yingu

The first partner sits right next to it, a little in front, toward the kneecap. With the knee bent, it is at the same inner end of the crease, in front of the two tendons rather than between them. In this tradition the two are commonly pressed together for an aching inner knee.

The second sits below the inner knee. Run your thumb up the inner edge of the shinbone from the ankle until it stops under the bony flare below the knee. The point is in that hollow. It is used with this one when the inner knee is stiff and the lower leg feels heavy.

The third is at the ankle, on the same line. Find the inner ankle bone and slide back into the hollow between it and the thick Achilles tendon. It is used with this one when the legs feel tired from the knee down to the heel.

How to Find and Press Yingu

Getting Into Position

Sit on a firm chair with the knee bent to roughly a right angle and the foot flat on the floor. Let the knee fall a little outward so the inner side faces your hand. If reaching is hard, cross the leg to be pressed over the other knee, or sit on a bed with the knee bent and the foot flat.

How to Find It

Reach around the inner side of the knee with your fingertips and find the crease at the back. Follow it toward the inner side. Near its end you will meet two cords running up and down. The lower one is thin and firm, like a pencil under the skin. The upper one is broader and softer. If you cannot feel them, press your heel down into the floor as if trying to drag it back toward the chair; the tendons will tighten. The groove between them, at the end of the crease, is the area.

Now probe it with a rounded-tip pressing tool, or the tip of your thumb with the nail cut short. Move slowly in small steps along the groove. Most of it will feel like ordinary tissue. One spot will sting: a small, sharp, pinpoint tenderness. That spot is the point. If you feel a strong pulse under the tip, you have drifted toward the middle of the knee; move back toward the inner side.

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 forward, toward the front of the knee, not toward the middle of the back of the knee. Rest your other hand on top of the knee to keep it still. Keep the tip on the same spot; do not let it slide off the tendons.

How Much Pressure

Sharp under the tool 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 the tool, if it spreads, or if the area turns swollen, hot or red, stop and leave it for several days. Stop at once if you feel throbbing, tingling or numbness. If you are holding your breath, you are pressing too hard. Ease off until you can breathe slowly through the sting.

How Long

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

When to Do It

Morning suits a knee that is stiff on waking and slow to straighten. Late afternoon suits a knee that has tightened after sitting or walking. Before bed is a good time too, as part of winding down. Do not press in the middle of the night. If an aching knee wakes you, pressing then tends to wake you further. Keep the pressing for the day and the evening.

What This Won't Do

It will not remove the reason your knee aches. With inner knee pain, the usual reasons are wear in the inner part of the joint, a torn or worn cartilage pad, weak thigh muscles, extra weight, or tight hamstrings that have not been stretched for years. A point at the back of the knee cannot rebuild any of that. Pressing works best alongside the plain things: gentle strengthening of the thigh, a daily stretch of the back of the leg, regular walking, and shoes that keep you steady.

It will not replace a diagnosis either. A knee that is suddenly hot, swollen and red needs to be seen, especially with a fever. So does a knee that locks, gives way, or will not take your weight after a twist. A lump behind the knee that grows needs to be checked. One calf that is suddenly swollen, warm and painful needs urgent assessment, because it can mean a clot in a deep vein. Pain that wakes you 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 if there is a swelling or lump behind the knee, swollen or bulging veins at the back of the knee, a recent injury, or a plate, pin or implant under the skin. Skip this point if the knee is hot and swollen, or if you had surgery on that knee recently, and ask your surgeon when you may start. If you take blood thinners, bruise easily, have a bleeding disorder, 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. Nothing here requires 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 Yingu (KI10) pressure point? Yingu (KI10) sits at the inner end of the crease behind the knee. Bend the knee and you will feel two tendons there, a thin firm one below and a broader, softer one above. The point is in the groove between them. In English it is called the Yin Valley; in Vietnamese, Âm Cốc.

How long should I press Yingu? 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 if only one knee aches.

How is Yingu (KI10) different from Ququan (LR8)? They sit side by side at the inner end of the knee crease. Yingu (KI10) is the one further back, between the two tendons. Ququan (LR8) is a little in front of them, toward the kneecap. Many people press both in the same sitting.

There is a soft lump behind my knee. Can I press here? No. Leave the area alone and have the lump checked. Fluid swellings behind the knee are common with worn knees, but a lump that grows, or one that comes with a swollen calf, needs a doctor to look at it first.

Is the back of the knee safe to press? The middle of the back of the knee carries a large artery and vein, so this page keeps to the inner end of the crease, between the tendons. If you feel a pulse under your tip, move toward the inner side. Keep the pressure moderate and stop if anything throbs or tingles.

Does it help with an ache along the inner thigh? In this tradition the point sits on a line that runs up the inner thigh, so it is often pressed when the inner knee and inner thigh ache together. Pain in the groin or inner thigh that comes on suddenly, or with a lump, should be seen by a 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: KI10 · Yingu · Yin Valley · Âm Cốc.)