A treatise on orthopedic surgery . transformation of deformed parts to the normal when theimproper relations of weight and strain have been first called attention to the fact that the shape of a boneis the effect of function. It is the effect of function in that ifthe work required of it had been different its shape would havebeen diftcreut. This function has shaped not only the externalcontour but the internal structure as well. If a bone is broken, DEFOBMITIES OF THE SPINE. 241 for example, the neck of the femur, and deformity results, theinternal architecture is no longer suit
A treatise on orthopedic surgery . transformation of deformed parts to the normal when theimproper relations of weight and strain have been first called attention to the fact that the shape of a boneis the effect of function. It is the effect of function in that ifthe work required of it had been different its shape would havebeen diftcreut. This function has shaped not only the externalcontour but the internal structure as well. If a bone is broken, DEFOBMITIES OF THE SPINE. 241 for example, the neck of the femur, and deformity results, theinternal architecture is no longer suitable for the new conditionsof weight and strain, and immediately a rearrangement begins,which finally transforms the internal structure, not only in theneighborhood of the injury, but in the extremity of the bonealso, to adapt the deformed part as well as may be to the workthat is now demanded of it. The normal bone is braced most thoroughly, and is most re-sistant at the points where most work is required of it. If the Fig. Normal femur from same subject. (Freiberg.) weight and strain are for any reason transferred to another part,its structure is strengthened there, and correspondingly weak-ened at the point from which the strain has been this change in the internal structure a change in the ex-ternal contour keeps pace. For, according to this theory, theexternal contour represents mathematically simply the last curveuniting the ends of the various trajectories which make up theinternal 242 OBTEOPEDIC SUEGEB¥. For the further exposition of this theory I quote from Frei-bergs-^ review and abstract of Wolffs^ final article. In showing that improper static demands made upon anextremity resulted in the formation of new masses of bone uponthe surface of the bone of this extremity, or that they producethe disappearance (atrophy) of bone masses according to thenature and degree of these disturbances in static requirements, Fig. 181.
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Keywords: ., bookauthorwhitmanr, bookcentury1900, bookdecade1910, bookyear1910
