Sacrum lumbar vertebra, and its lower part with the coccyx (tailbone) via the sacral and coccygeal cornua. The sacrum has three different surfaces which are shaped to accommodate surrounding pelvic structures. Overall it is concave (curved upon itself). The base of the sacrum, the broadest and uppermost part, is tilted forward as the sacral promontory internally. The central part is curved outward toward the posterior, allowing greater room for the pelvic cavity. In all other quadrupedal vertebrates, the pelvic vertebrae undergo a similar developmental process to form a sacrum in the adult, even while the bony tail (caudal) vertebrae remain unfused.
Traditional Chinese medicines derived from the human body pharmacopoeias continue to list human drugs. Within their sample of 8 human drugs, prescriptions mention two dozen symbolic ritual procedures (1973: 265). Sympathetic magic, for example, could explain using blood to treat blood loss (52.17.3 above) and attempting to treat bone damage with bone (52.27.1). Li Shizhen quotes the (9th century) "Miscellaneous Morsels from Youyang". The book "Youyang Zaju": Once a military man in Jingzhou had an injured tibia. Doctor Zhang Qizheng treated him with a kind of medicinal wine, which was taken orally. A small segment of broken bone in the wounded tibia was taken out and a kind