Xiyan Xīyǎn

Reviewed by · Licensed Acupuncturist & TCM Physician · Last reviewed June 2026

Xiyan (Xīyǎn, “Xīyǎn”) is an extra (non-channel) acupuncture point. It is located on the knee, in the two depressions medial and lateral to the patellar ligament, found when the knee is flexed. These are a pair of points, one on each side of the patella. It dispels wind-damp, reduces swelling, alleviates pain, and opens the channels and collaterals of the knee.

Location

On the knee, in the two depressions medial and lateral to the patellar ligament, found when the knee is flexed. These are a pair of points, one on each side of the patella.

Needling

With the knee flexed, perpendicular insertion 0.5-1.0 cun. Oblique insertion medially and inferiorly into the joint cavity is also common. It is often needled through-and-through from the lateral point (Dubi/ST35) to the medial point.

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TCM functions

Dispels wind-damp, reduces swelling, alleviates pain, and opens the channels and collaterals of the knee..

Indications

Knee pain, unceasing cold in the knee, knee swelling, leg and knee pain, difficulty walking, leg weakness, foot weakness (beriberi), leprosy, general sores,crane's knee wind, leg and foot heaviness and pain..

Clinical notes

Xiyan, comprising the medial and lateral 'eyes' of the knee, is a primary local point for any knee disorder. It is especially effective for pain, swelling, and stiffness associated with arthritis, injury, or wind-damp bi-syndrome. The classical sources show a significant conflict regarding moxibustion; while some forbid it and warn of dire consequences, others explicitly recommend it for conditions like foot weakness and leprosy. This suggests that the appropriateness of moxibustion may depend on the specific diagnosis, with caution advised in cases of acute inflammation or severe swelling.

Frequently asked questions

Where is Xiyan located?

Xiyan (Xīyǎn) is located on the knee, in the two depressions medial and lateral to the patellar ligament, found when the knee is flexed. These are a pair of points, one on each side of the patella.

What is Xiyan used for?

Xiyan dispels wind-damp, reduces swelling, alleviates pain, and opens the channels and collaterals of the knee. Common clinical indications include knee pain, unceasing cold in the knee, knee swelling, leg and knee pain, difficulty walking, leg weakness, foot weakness (beriberi), leprosy, general sores,crane's knee wind, leg and foot heaviness and pain.

How is Xiyan needled?

With the knee flexed, perpendicular insertion 0.5-1.0 cun. Oblique insertion medially and inferiorly into the joint cavity is also common. It is often needled through-and-through from the lateral point (Dubi/ST35) to the medial point. Caution: The Zi Sheng Jing strongly forbids moxibustion, citing a case where a person with severe knee swelling died after receiving moxibustion at this point. This contrasts with other sources that recommend it for specific conditions.

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⚠️ This page is for general education and is not medical advice. Acupuncture is a traditional practice; evidence varies by condition and study quality, and individual results differ. It does not replace diagnosis or treatment by a licensed professional. Always consult a qualified acupuncturist or physician.