Orthopædic surgery : a handbook / by Charles Bell Keetley.

  • Keetley, Charles Bell.
Date:
1900
Catalogue details

Licence: In copyright

Credit: Orthopædic surgery : a handbook / by Charles Bell Keetley. Source: Wellcome Collection.

Provider: This material has been provided by UCL Library Services. The original may be consulted at UCL (University College London)

    28/570 page 6
    than guessed at, and does not admit of anything approaching to proof at all. As with osteomalacia, so also with rickets, either rachitis infantum or rachitis adolescentium ; and so also with osteitis deformans and with tabetic joint diseases. But even the influence of the weight-pressure in the manner above acknowledged is not allowed to hold the field undisputed. To make this matter clear some remarks on the structure of bone will assist. The beautiful fitness of the internal architecture of bones for their functions has long been known, and was described by Holden in the following words: The cancellous tissue 'is formed by the separation of the component layers of the bone, and these are ctDnnected by cross-plates or columns, so as to form a kind of lattice-work. The direction of these component layers in all parts of bones is arranged upon this principle : they always run exactly in the line of lyresmrc which the hone has to hear. A beautiful examj)le of this is seen in the section of the cancellous tissue of the thigh-bone. At the lower part, towards the knee, the layers run vertically—^that is, in the direction of the axis of the shaft.' ' But in the neck of the thigh-bone the layers are arranged in the form of arches, one within the other, in order to sustain with the greatest mechanical advantage the weight transmitted on to the heads of the thigh-bone.' ^ These obser- vations had been made long before Holden's time, but some Continental writers erroneously attribute the original exposi- tion of the facts to Meyer of Zurich, who wrote about the in- ternal structure of the calcaneum and of the neck of the femur in 1869. It had also been frequently observed, especially in connection with the ultimate condition of bones which had, after fracture, united more or less at an angle, or which became ankylosed together after disease of an intervening joint, that the process of repair was conducted with an eye, so to speak, to the internal arrangement of the uniting bone in an economical and workmanlike manner. In 1884, Professor Julius Wolff, of Berlin, laid down as a law of Nature that the internal architecture of hones altered by disease is modified in corresjJOiidence ivith the chanc/ed statical conditions. This is Wolff's ' Transformationsgesetz.' Further, • Holden's Osteology, 1st edition (1855), with illustrations, p. 8.
    digitised image 1
    digitised image 2
    digitised image 3