A quiet but useful point on the back of the knee. Fuxi (BL-38) relaxes the local sinews, eases tightness and numbness in the thigh and popliteal region, and is one of the Bladder channel's dedicated points for the lower limb.
Name & story
The name 浮郄 Fuxi is usually rendered as 'Floating Cleft' — 浮 (fu) means floating or superficial, and 郄 (xi) means a cleft or gap, often referring to a hollow between sinews. The image is of a small, somewhat hidden hollow sitting just above the great popliteal crease, as if lightly floating above the deeper Weizhong (BL-40) below it. It is not a Xi Cleft point in the formal category sense, but its name carries the same sense of a gap or depression where Qi can be accessed.
Point family & character
Fuxi (BL-38) belongs to the Bladder Meridian (BL). It is a local point of the popliteal region, sitting just above the better-known Weizhong (BL-40) on the posterior thigh. It is part of the group of Bladder channel points on the lower limb, whose general focus is disorders of the lumbar region, anus and leg.
Location
On the posterior aspect of the thigh, 1 Cun above Weizhong (BL-40), just medial to the tendon of the biceps femoris muscle. It is found at the upper border of the popliteal crease, slightly toward the lateral edge.
Anatomy & fascia
The point lies in the region of the biceps femoris muscle and its tendon, at the upper border of the popliteal fossa. The popliteal vessels and the tibial nerve are present in this region, so care is warranted.
Needling
The needle is inserted perpendicularly. Careful technique is needed in this region because of the proximity of the popliteal vessels.
Moxa, cupping & Tui Na
Gentle massage or acupressure over the point can help relax tightness in the back of the knee and thigh. Warmth may be applied with care in Cold or deficiency patterns affecting the local sinews.
Functions
Relaxes the sinews and eases pain in the popliteal region and posterior thigh; benefits the lower limb; addresses numbness and contraction in the local area.
Indications
Tightness, contraction or numbness of the popliteal region and posterior thigh. Pain and stiffness in the back of the knee. Weakness or heaviness of the lower leg. Disorders of the lower limb in general. As a Bladder channel point in the thigh region, it also has relevance to lumbar and lower limb disorders in keeping with the broader channel pathway.
Point combinations
Often considered alongside Weizhong (BL-40) directly below it, for problems of the popliteal fossa and posterior leg. It may be paired with other local and distal Bladder channel points for lumbar and lower limb conditions.
Clinical spotlight
Fuxi (BL-38) is one of the less-frequently discussed points on the Bladder channel, but it holds a clear niche: problems that are specifically located in the upper popliteal region and posterior thigh — tightness of the biceps femoris tendon, numbness or contraction just above the knee crease — where the more famous Weizhong (BL-40) sits slightly too low. Clinicians familiar with the posterior thigh often choose Fuxi when the presentation is localised to that band of tissue just above the knee fold.
The golden tip
To find this point, reach behind your knee and feel for the large tendon on the outer side (the biceps femoris); Fuxi sits about one thumb-width above the back-of-knee crease, just beside that tendon. Gentle finger pressure here can help ease tightness or a heavy feeling in the back of the knee after long periods of sitting or standing. Take care not to press too hard into the deeper tissues of the popliteal fossa.
For education only — not medical advice. Consult a qualified practitioner.