BONE, PATHOLOGICAL CONDITIONS OF. 



447 



poses the fracture to remain for a considerable 

 time un-united, the limb being, of course, 

 weaker here, so that, in the event of the occur- 

 rence of a new fracture, this will be the spot 

 in which it will give way. The second or per- 

 manent callus, which he calls " cal definitif," 

 is the actual medium of union between the 

 fragments, and remains like the cicatrix of a 

 wound in the soft parts. 



It must appear curious to the reader that no 

 positive conclusion should have been obtained 

 on a point which has occasioned so much 

 inquiry, and which apparently was so easy of 

 determination. It is open to experiment; 

 obvious to the senses ; and there are few 

 sources of fallacy except such as might arise 

 from previously adopted views of the expe- 

 rimentalist, and perhaps from different periods 

 puring the progress of ossification being chosen 

 for making the observations, and the same 

 thing, of course, being seen under different 

 circumstances. We think it might have been 

 reasonably suspected from analogy, (and the 

 experiments of Breschet and Villerme have 

 confirmed the idea,) that nature, in the sim- 

 plicity of her operations, produced every where 

 similar effects from similar causes, and that, 

 in whatever manner the re-union of divided 

 soft parts was accomplished, the same would 

 hold good as to bone, only allowing a longer 

 time in order to admit of the consolidation of 

 the lymph by osseous deposition. And such 

 is probably the fact. In an incredibly short 

 space of time after the receipt of a fracture, 

 the process of repair seems to be actively com- 

 menced : coagulating lymph is effused in con- 

 siderable quantity, probably mixed with blood, 

 as the coagulum is found to possess a more 

 than ordinary firmness and consistence. At 

 the end of the second day the torn edges of 

 the periosteum are evidently thickened, pulpy, 

 and vascular, easily receiving coloured in- 

 jections. At the end of the fourth day, we 

 have seen the sharp edge of the fracture be- 

 ginning to be rounded off. Where the surfaces 

 of the fragments are broad and thick, it is easy 

 to observe them coated with a deep layer of 

 lymph, which adheres to them tenaciously from 

 a very early period. If the fragments are in 

 apposition, the torn extremities of the peri- 

 osteum are united by the intervention of this 

 lymph, the membrane appears greatly thick- 

 ened also, and seems to afford a kind of pro- 

 tection to the fracture ; or, otherwise, an im- 

 mense and irregular mass of lymph is thrown 

 out around both fragments, filling up all the 

 space that has been occasioned by the dis- 

 placement of the bones and the laceration of 

 the soft parts. In effecting this deposition, all 

 the vessels of the part, those of the bone, 

 periosteum, and adjacent structures, seem to 

 be equally engaged. In process of time this 

 lymph becomes organised, assumes a ligamen- 

 tous rather than a cartilaginous appearance, 

 although, strictly speaking, the new structure 

 possesses not the true characters of either, and 

 finally is converted into bone by the simul- 

 taneous establishment of numerous but irre- 

 gular specks of ossification. This process 



varies as to the time required for its com- 

 pletion according to a number of circum- 

 stances, such as the situation of the bone, the 

 part of it broken, the apposition of the frag- 

 ments, rest, and many others that need not be 

 enumerated here ; as well as the age and con- 

 stitution of the patient, which exert such 

 marked influence on all cases, that it is im- 

 possible to lay down certain rules for calcu- 

 lating the time that may be required for the 

 union of any given fracture. 



The process of re-union, however, is some- 

 times very imperfectly performed ; sometimes 

 it is suspended indefinitely, and occasionally 

 it is not performed at all. Of the causes that 

 occasion these deviations from the natural and 

 usual progress of ossific union we are in ge- 

 neral ignorant, although there are many cases 

 in which former experience may enable us to 

 predict the occurrence of such an event. It 

 has been already stated that the diseases which 

 occasion a fragility of bone will be likely to 

 interfere with its subsequent union, and in 

 these cases little more is accomplished than the 

 removal of the sharp spiculated edges by ab- 

 sorption : the presence of such a constitutional 

 derangement as would occasion a bone to give 

 way in the effort to turn in bed will be suf- 

 ficient to explain its want of re-union. But 

 these are not the cases generally met with. 

 When there is an un-united fracture, or as it 

 has been termed, a false joint, the ends of the 

 fragments are not smooth and polished moving 

 on each other like articulated surfaces, but are 

 joined together by the intervention of a liga- 

 mento-carti'.aginous substance, which, accord- 

 ing to its extent, is more or less flexible, and 

 of course incapacitates the bone from the per- 

 formance of its functions of support and mo- 

 tion. This imperfect union occurs in some 

 bones with wonderful regularity; we may, for 

 instance, calculate on such an event in frac- 

 tures of the neck of the thigh, and in the trans- 

 verse fracture of the olecranon and patella ; 

 but it happens at other times quite unexpect- 

 edly, iu cases wherein we could suspect no 

 possible cause, in which there may have been 

 no neglect, no impropriety of treatment, to 

 lead to such a result. We have lately seen 

 two cases of fractured femur remain un-united 

 at the end of five and six months in the per- 

 sons of fine and apparently healthy young 

 men, although the ends of the bones were kept 

 in apposition, and in every other respect the 

 treatment was correct. 



The chief causes* to which this imperfect 

 union has been attributed are a removal, or 

 rather a withdrawing of the broken surface of 

 one fragment from the other, a want of vascu- 

 larity in one of the fragments, and the fracture 

 not being maintained in a slate of uninter- 

 rupted repose. 



The frequency of this occurrence in fractures 

 of the above-mentioned bones, in which the 

 fragments are always withdrawn from each 

 other, was too remarkable not to lead to the 

 connexion of the circumstances as cause and 



* Sir A. Coopov 011 Dislocations and Fractures. 



