Shuiquan

What is KI5?

KI5 (Shuiquan) sits on the inner ankle, a thumb-width below the hollow between the ankle bone and the Achilles tendon.

The name Shuiquan is usually translated as "Water Spring". In traditional Chinese medicine it is the xi-cleft point of the Kidney channel. Xi-cleft points are the ones classical texts reach for in sudden, sharp or acute problems, rather than long-term tonifying.

Traditionally KI5 is associated with menstrual complaints: period pain, late or absent periods, and irregular cycles. It is also linked in older texts to difficulty passing urine and to a feeling of fullness low in the abdomen. Those are the claims of a system of thought, not findings from a laboratory.

Here is the honest verdict on the evidence. There is no good human research on pressing KI5 for anything. The acupressure literature as a whole is mostly small, short and unblinded, meaning few participants, brief follow-up and participants who knew what they were getting. For KI5 specifically, even that thin layer is largely missing. A handful of acupuncture trials for period pain have included Kidney channel points in a wider prescription, which tells us nothing about this single point under a fingertip.

Two things are worth stating once, clearly, and they apply to every section that follows. First, a long traditional pedigree is not evidence that a point does anything. Points have been taught for centuries on the strength of theory and observation, not controlled comparison. Second, that pedigree is not evidence of safety either. "Ancient" does not mean harmless, and the safety notes on this page come from anatomy and common sense, not from tradition.

What KI5 can reasonably be: a specific, easy-to-find spot for a few minutes of self-applied finger pressure, which many people find calming and mildly pain-distracting. What it is not: a treatment, a cure, or a substitute for working out why a symptom is happening.

Everything described on this page is finger pressure on unbroken skin. Nothing here involves needles, heat or anything that breaks the skin.

Where is KI5 and how do you find it?

KI5 lies on the inside of the ankle, about one thumb-width below KI3, in a small dip in front of and above the heel bone's inner knob.

• Sit so you can reach your ankle. Cross one ankle over the opposite knee, or sit with your foot flat and lean forward. You want to see and feel the inner side of the ankle clearly.
• Find the inner ankle bone. That is the medial malleolus, the round bump on the inside of your ankle. Put a fingertip on its highest point.
• Slide back to the hollow. Move your finger straight backwards, towards your heel. You drop into a soft hollow between the ankle bone and the hard cord of the Achilles tendon. That hollow is KI3, the usual starting landmark.
• Drop down one thumb-width. From that hollow, move down towards the sole about 1 cun. One cun is the width of your own thumb at the knuckle, roughly 2 to 2.5 cm for most adults.
• Feel for the small dip. You should land in a slight depression just in front of and above the inner knob of the heel bone (the medial calcaneal tubercle). Press gently and move a few millimetres around until you find the tender, slightly hollow spot. That is KI5.

Use your own thumb as the ruler, not someone else's. Cun is a proportional measure, so a tall person's thumb-width is correctly bigger.

You may feel a pulse nearby. The posterior tibial artery runs through this region behind the ankle bone. If you feel a steady throb under your fingertip, ease off and shift slightly forward or down; you are not meant to be compressing a pulse.

Landmarks vary slightly between textbooks, so treat the dip below and in front of the KI3 hollow as the agreed description. If you cannot feel a clear hollow, stay in the soft tissue and avoid pressing hard on bone.

How do you apply pressure to KI5?

1. Settle first. Sit comfortably with the ankle supported and the foot relaxed. Tense muscles make the hollow harder to feel and the pressure less comfortable.
2. Use a thumb or index finger. Place the pad of the finger, not the nail, on the dip you located. A small, soft contact area works better than a hard point.
3. Press straight in, gently. Build pressure slowly over a few seconds until you feel a dull ache or a firm, satisfying sensation. Aim for about 3 or 4 on a 10-point discomfort scale. Sharp, bright or shooting pain means too hard or off the spot.
4. Hold or circle. Either hold steady pressure for 20 to 30 seconds, or make small slow circles for the same time. Keep breathing normally; do not hold your breath.
5. Release and repeat. Ease off for 10 seconds, then repeat. Three to five rounds per ankle is plenty for one session.
6. Do both sides. Tradition treats the point bilaterally. Give each ankle roughly equal time.
7. Keep sessions short. Two to three minutes per ankle, once or twice a day, is a reasonable ceiling. Longer is not better and increases the chance of bruising tender skin.

Stop immediately if you feel a pulse throbbing under the finger, numbness, pins and needles, or pain that travels into the foot. Shift position or stop for the day.

Do not press through clothing you cannot feel landmarks through, and do not use hard tools, pressure pens or knuckle-digging here. The ankle has little padding, and nerves and vessels run close to the surface on the inner side.

If the area is sore the next day, skip a session. Tenderness that lingers more than a couple of days is a reason to leave the point alone and look for another explanation.

What is KI5 traditionally used for?

• Period pain. This is the main classical use. As a xi-cleft point, KI5 was chosen for sharp, cramping menstrual pain. Human evidence for pressing KI5 itself is absent. Acupressure for period pain has been studied mostly at SP6 on the lower leg, with small, unblinded trials suggesting modest short-term relief; those findings do not transfer to KI5.
• Irregular, late or absent periods. Traditional texts list KI5 for cycles that arrive late or stop. There is no human trial testing finger pressure at this point for cycle regularity, and no plausible evidence it changes hormones. Absent or newly irregular periods need a medical explanation, not a pressure point.
• Lower abdominal fullness or dragging. Tradition describes KI5 for a heavy, blocked feeling low in the belly. This is a theory-based use with no supporting trials.
• Difficulty passing urine. The "Water Spring" name links the point to urinary flow in classical thinking. No human research supports using it this way. Straining to pass urine, or being unable to, is a medical problem and can be an emergency.
• A calming, grounding few minutes. The most defensible thing to say is the least dramatic. Slow, attentive pressure on a tender ankle spot is pleasant for many people and can take the edge off how distressing a symptom feels. That is a general effect of touch and attention, not something specific to KI5.

Across all of these, the gap is the same: tradition is detailed, human testing is essentially missing. Where acupressure has been tested properly for a symptom, the trials usually used a different point.

Treat KI5 as something you can try alongside whatever is actually managing the problem, such as pain relief, heat, or investigation of why the cycle has changed. It is not a replacement for any of those.

What might regular use of KI5 help prevent?

• Pre-period use is traditional, not proven. Some practitioners suggest working the point in the days before a period is due, hoping to blunt cramps before they start. No human study has tested whether this prevents anything.
• No evidence it prevents cycle problems. Regular pressure at KI5 has not been shown to make irregular periods regular, prevent missed periods, or affect fertility in any way.
• No evidence it prevents urinary problems. Despite the "Water Spring" name, nothing supports using KI5 to head off urinary infections, retention or incontinence.
• A routine may still be worth something. A short daily habit of sitting down, breathing slowly and pressing a tender spot can help some people feel less braced against a recurring symptom. That is a benefit of the routine, not a preventive effect of this point.

The honest summary is that KI5 has no credible prevention evidence behind it. If you want to try it as part of a pre-period routine, there is little to lose on unbroken skin, but do not delay investigating a cycle that has genuinely changed.

Are there tips for using KI5 effectively?

• Find KI3 first, then step down. The hollow between the inner ankle bone and the Achilles tendon is much easier to feel than KI5 itself. Locate that, then move one thumb-width down towards the heel.
• Let tenderness guide you. KI5 is often slightly sore when you find it. If an area a few millimetres away feels more distinctly tender and hollow, that is usually the better contact point.
• Warm the ankle beforehand. A warm shower, a sock on for ten minutes, or simply rubbing the ankle makes the tissue softer and the landmarks easier to feel.
• Use less force than you think. The inner ankle is thinly padded. Firm is useful; grinding into bone is not, and it bruises.
• Keep the foot relaxed. Pointing or flexing the foot tightens the tendons and changes the landmark. Let the foot hang loose.
• Avoid the pulse. If you feel a throb, move slightly away from it. There is no benefit to pressing on an artery, and it is uncomfortable.
• Keep expectations small and specific. Judge it on whether the next few minutes feel more comfortable. Do not expect a changed cycle or a resolved symptom.
• Track it honestly. If you use it for period pain, note pain before and after, and whether you also took medication or used heat. Otherwise you cannot tell what helped.
• Keep doing what works. Pain relief, a heat pack, movement and sleep all have better support for cramps than any pressure point. Use KI5 alongside them, not instead.

One practical point: trim or file the nail on the finger you use. A long nail turns gentle pressure into a scratch on thin ankle skin.

What do people get wrong with KI5?

• Expecting a cure. The single biggest error. KI5 will not fix a menstrual disorder, restore a missed period or treat a urinary problem. Anyone promising that is overselling it.
• Pressing KI3 and calling it KI5. They are close neighbours. KI3 is the hollow level with the ankle bone tip; KI5 is roughly one thumb-width below it, nearer the heel bone. Confusing them is the most common location error.
• Landing on bone. People slide too far back onto the heel bone or too far up onto the ankle bone. You want the soft dip in front of and above the inner heel knob, not the hard surface itself.
• Pressing on a pulse. If you feel rhythmic throbbing, you are over the posterior tibial artery. Move off it. Sustained pressure there is uncomfortable and pointless.
• Using tools or knuckles. Pressure pens, massage sticks and hard knuckles concentrate force on a thinly padded area and cause bruising. Fingertips only.
• Going too hard for too long. Ten minutes of deep digging does not beat thirty seconds of moderate pressure. It just leaves the ankle sore.
• Working over swollen or injured skin. A sprained, swollen, hot or bruised ankle should be left alone and assessed, not pressed.
• Delaying a diagnosis. Using KI5 for weeks while periods stop, pain worsens or urination becomes difficult is the mistake with real consequences.
• Treating tradition as proof. That KI5 appears in every point textbook says it has been taught for a long time. It does not say it works.

If you are unsure you are on the right spot, stay conservative. Gentle pressure anywhere in that soft hollow is harmless on healthy skin; forcing a landmark you cannot feel is not.

What does the research on KI5 actually say?

There is essentially no human research on KI5 as a standalone point, and none at all on pressing it with a finger.

Searches of the acupuncture and acupressure literature turn up no controlled trial in which KI5 was the point under test. Where Kidney channel points appear in studies, they are usually one item in a multi-point acupuncture prescription for period pain or urinary symptoms. In that design, the needles were placed by a practitioner at several sites at once, so nothing can be concluded about KI5 alone, and nothing at all about self-applied pressure.

It is worth being clear about what published acupuncture trials involve, because readers sometimes see them cited for acupressure. Those trials insert needles. That is a clinical procedure performed by a trained practitioner, and it is not what this page describes or recommends. Reporting what a trial did is different from telling you to do it.

The wider acupressure evidence base has one genuinely strong example, and KI5 is not it. PC6 at the wrist has repeatedly been tested for nausea and vomiting, including in pregnancy, after surgery and during chemotherapy, with reasonable evidence of a real if modest benefit. That body of work shows good acupressure research is possible. Its absence around KI5 is therefore informative, not just a gap waiting to be filled.

For menstrual pain specifically, the better-studied acupressure point is SP6 on the inner lower leg. Trials there are small, usually unblinded and short in follow-up, and they suggest modest short-term pain reduction. Those results belong to SP6, and it would be dishonest to lend them to KI5.

What this means practically: treat KI5 as untested. Gentle self-pressure on healthy skin carries little risk, so trying it is reasonable. But judge it only by how you feel in the following minutes, keep using the treatments that do have evidence, and get a persistent or worsening symptom properly assessed.