Book One -- The things that sustain and support the entire body, and what braces and attaches them all. [the bones and the ligaments that interconnect them] | Chapter 18 On the Sacral Bone and the Coccyx

Galen’s opinion about the sacrum and coccyx

In De usu partium, the sacrum is mentioned more than once. It is said there to be constructed of four bones, but not a syllable is devoted to the coccyx. 12 And besides the fact that Galen does not mention the coccyx there, it is abundantly clear that it was unknown to him when he wrote that book. For while explaining that there are four bones of the sacrum, he adds that a cartilage (c in figs. 2 and 3) is attached to their end, which we shall state in the course of our account grows upon the point of the coccyx; 13 the ends of bones that are not attached to another bone almost always revert into this cartilage. Moreover, in the twelfth book of De usu partium, he asserts that the transverse processes of the sacrum [pars lateralis] (L, L, R in fig. 1 and 2) are thin and delicate, while in De ossibus he teaches that they are thick and broad (as indeed they are). 14 But in his book De ossibus, which he wrote after De usu partium when he had become more skilled in the dissection of monkeys, Galen reckons that the sacrum is formed of three bones (nos. 1, 2, 3 in fig. 4); 15 brief as that book’s description of the bone is, it elegantly and perfectly fits the sacrum of monkeys and dogs. He then enumerates three other ossicles (nos. 4, 5, 6 in fig. 4) beneath the three bones of the sacrum, collectivly called by him the coccyx and briefly described as they are in monkeys. 16 In De anatomicis administrationibus, which he wrote last of all his books of anatomy, as always he deals more with the construction of the ape than of man; thus he mentions the sacrum and the coccyx in such a way that his account does not differ at all from that in De ossibus. 17 When he counts among the muscles that move the femur the one that he says originates from the coccyx (F in the 11th table of muscles), 18 it is quite readily deduced that he is referring to the three ossicles [vertebrae coccygeae I-III] that come in apes below the third bone of the sacrum. 19 Yet in De usu partium, (where he depends to a great degree upon the views of other anatomists) he wrote that this muscle originates from the sacrum (as you will hear happens also in man). 20 So that you may more easily follow the doctrines of Galen and likewise judge the negligence of those who will foolishly copy things they have never seen from the books of others, I shall be glad now to describe both the sacrum and the coccyx as they are in apes and dogs, and afterward begin my account of human bones.



Book One -- The things that sustain and support the entire body, and what braces and attaches them all. [the bones and the ligaments that interconnect them] | Chapter 18 On the Sacral Bone and the Coccyx