SP-9 Yinlingquan (陰陵泉) — Yin Mound Spring

In the depression distal to the medial condyle of the tibia, at the transition from the medial condyle to the body of the tibia, in front of the belly of the gastrocnemius muscle (at the same level as GB-34).

Seated with the knees flexed, or supine, locate the point in the posteroinferior depression of the medial condyle of the tibia, at the level of the inferior margin of the tibial tuberosity.

Medial head of the gastrocnemius, insertion of the sartorius, gracilis, and semitendinosus muscles (pes anserinus). Innervated by the saphenous nerve.

Perpendicular insertion, 1.0–1.5 cun.

Yin (阴), medial aspect; Ling (陵), mound; Quan (泉), spring, fountain. The interior is Yin. The point lies in the depression at the inferior margin of the medial condyle of the tibia, like a spring at the base of a mound.