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 3 Names by which the Parts and Surfaces of Bones are Identified

E)pi/fusij: epiphysis 22

E)pi/fusij, which Latin writers translate appendage, insertion, attachment, accretion, growth, and undoubtedly countless other ways, I shall always Latinize as appendix. An epiphysis is a bone grown onto another bone; it has its own border and is not a true part of the bone to which it is attached. It is possible to learn the nature of such an epiphysis whenever part of a calf, kid, lamb or any young animal is put on the dinner table. When a femur, humerus, tibia, radius, ulna, or similar bone has been cleaned of other matter and handled a little roughly, we see as it were another bone fall from it. That is called the epiphysis, and we see it only in younger animals. With age, the epiphyses grow so tenaciously to their bones that they cannot be torn away. 23 They barely show the line where they are joined, and they seem to be an actual part of their bones, while in recently born animals one sees a large amount of cartilage 24 between the epiphysis and the bone to which it is attached, which binds epiphysis to bone like glue. This juncture is not accomplished along a smooth or even surface; rather, the bone to which the epiphysis is joined abounds in cavities and rough spots [centers of ossification], to which the cavities and tubercules of the epiphysis are the more strongly fitted by mutual accommodation. This connection is also unique in that no bone is softer than in precisely this area; the bone is seen to be harder and more solid outside of the connection itself. For in that place bone is always full of pores inside, like pumice or sponge [cancellous bone]; and though the bone often has a single large, hollow cavity along most of its length filled only with marrow and is extremely hard and strong along the length of this cavity, nonetheless the cavity stops before the bone is joined to the epiphysis, and the bone becomes softer and full of pores, like the epiphysis itself. 25



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 3 Names by which the Parts and Surfaces of Bones are Identified