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 4 On the Structural Relationships of Bones

Some major disagreements in this chapter with the opinions of Galen 55

I had intended to put an end to this chapter and direct my account to descriptions of individual bones, had not the authority of Galen greatly delayed me; but it justly prevents me from so lightly passing by matters which in the present chapter diverge from his opinions. From many opinions besides those already mentioned, I would cite something, first in his book De ossibus, where he straightforwardly (and with no modest self-praise

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in the first Book of De administrandis sectionibus) enumerates the structures of bones: 56 I have not agreed with his doctrine in which he teaches that suture, harmonia, and gomphosis are types of synarthrosis. 57 For I have ascribed to synarthrosis an obscure and not obvious movement, and I have stated that synarthrosis and diarthrosis are made by the same varieties and forms of articulation. I have given suture, harmonia, and gomphosis not an obscure and difficult motion, but no motion whatever, and I have by no means included these types of connection, with Galen, in the category of joints. He would assuredly not have done so, unless in explaining severally the construction of the carpal, metacarpal, tarsal, and metatarsal bones, and the costal cartilages with the sternum, he had wished to state falsely 58 that these are joined by synarthrosis. For when he was saying correctly 59 that these bones are attached by synarthrosis, should he not have noticed that they are not connected by suture, harmonia, or gomphosis? This certainly would have been the case if he had been correct in determining that harmonia, suture, and gomphosis are types of synarthrosis. But as I see it, it will be a simple matter for anyone to make up his own mind about synarthrosis, as long as he bears in mind that it is construed quite differently in almost all the books of Galen than it is in the beginning of his book De ossibus. Even in Chapters 13, 19, 21, and 24 of the same book, Galen feels differently than at the beginning. Moreover, the author of Introductorius seu Medicus, not accepting the opinion of Galen and dividing the connections of bones in his own way, says: “The bones are put together either for motion, and this type of construction is called arthron or joint; or for no motion, and they are called synarthrosis.” He lists their types as suture, gomphosis, and symphysis. 60 But by this account synarthrosis cannot in any way be accommodated to the makeup of the carpal, metacarpal, tarsal, and metatarsal bones, since they are connected to each other by neither suture nor gomphosis, and much less by symphysis.

I have also departed further from Galen’s opinion in saying that all attachments of bones are either aided by some substance, 61 or by none; Galen attributed this only to symphysis in De ossibus, and he counted synneurosis, syssarcosis, and synchondrosis only as types of symphysis. 62 His own account gave me the first reason for not following him, where he taught that soft, spongy bones [ossea spongiosa] are attached to each other by symphysis with nothing in between, but drier and denser bones [ossea compacta] come together by means of intermediate materials. 63 For I learn that in bones which are still soft and tender, epiphyses are united to their bones by cartilage [cartilago epiphysialis], while in hard, dry bones and bones of old people, nothing at all assists symphysis. Moreover, I can find absolutely no symphysis or union that one could truly say was made with the aid of a ligament; synneurosis could not therefore be included under symphysis, bearing in mind that no union [symphysis] is completed by aid of a ligament in the way that articulations all certainly come together with the aid of a ligament, in some cases (as I have said before) wrapped around the joint, in others coming between the two bones where they meet [articulationes synoviales]. As I considered each case exactly, I found still less symphysis where one would rightly say the attachment was made by flesh. For in no connection of bones does flesh [textus connectivus] play a role unless perhaps in the connection [periodontium] of teeth with the maxillae, which is judged to be gomphosis, not symphysis; and however immobile the teeth, they are not more so than in harmonia or suture. But on the other hand almost all articulations are held together with the help of flesh, i.e., of muscles. We have said that this bond was called syssarcosis 64 by the ancients. No one could say this is a species of symphysis.

In addition to this (so that an end may finally be put on this chapter), a passage in the second book of Aristotle’s De partibus animalium has warned us the more quickly to disagree with Galen, where Aristotle affirms that the bones are joined by nerves, 65 flesh, and cartilage, very learnedly assigning this connection categorically to all meetings of bones. 66 Yet Galen knowingly passes over this very opinion of Aristotle when, forgetful of the things he taught in his book De ossibus, he runs through the structure of bones in a perfunctory though quite elegant way at the end of the second Book of De administrandis sectionibus, more or less summarizing the words of Aristotle. 67

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 4 On the Structural Relationships of Bones