Astanga Hrudaya
जङ्घाचरणयोः सन्धौ गुल्फो रुक्स्तम्भमान्द्यकृत्। जङ्घान्तरे त्विन्द्रबस्तिर्मारयत्यसृजः क्षयात्॥५॥
At the junction of the calves and foot is gulpha, its injury causes pain, stiffness (or loss of control) of the leg or loss of activities. In the centre of the calf muscle is indrabasti, its injury leads to death by (severe) loss of blood.
english translation
jaGghAcaraNayoH sandhau gulpho rukstambhamAndyakRt। jaGghAntare tvindrabastirmArayatyasRjaH kSayAt॥5॥
hk transliteration by Sanscript