Astanga Hrudaya
वंशाश्रिते स्फिजोरूर्ध्वं कटीकतरुणो स्मृते। तत्र रक्तक्षयात्पाण्डुर्हीनरूपो विनश्यति॥१८॥
attached (embedded in) to the spine, above the buttocks, are the two katikataruna; injury to these causes pallor due to loss of blood, emaciation, and death.
english translation
vaMzAzrite sphijorUrdhvaM kaTIkataruNo smRte। tatra raktakSayAtpANDurhInarUpo vinazyati॥18॥
hk transliteration by Sanscript