BONE, PATHOLOGICAL CONDITIONS OF. 



446 



surface of a stump or other wound covered 

 with clotted blood, and spare ourselves all the 

 labour and pains we employ in removing it 

 and placing the cut surfaces cleanly in appo- 

 sition with each other. And they also remark 

 that when a clot of blood is left behind, how 

 very commonly, instead of becoming organised, 

 it lies as a dead substance in the wound, im- 

 pedes the union, promotes suppuration, and 

 imparts to the discharge a putrid and offensive 

 odour. These pathologists suppose that in 

 many instances the fi brine of the blood has 

 been mistaken for coagulating lymph, which 

 is the natural product of the vessels in the 

 adhesive stage of inflammation, is capable of 

 becoming organised, and ought to be the legi- 

 timate seat of any deposit to be afterwards 

 laid down in completing the process of union. 



We now pass to the theory of Bordenave, 

 Bichat, and Richerand, who make the union 

 of fractures analogous to that of the soft parts 

 by the second intention, or by means of 'granu- 

 lation. Like other pathologists, they have 

 supported their opinions by observation and 

 experiment; and without 'entering into the 

 minuter circumstances connected with this hy- 

 pothesis, it will be necessary to mention some 

 very familiar facts that bear upon the case. 

 In necrosis, the surface of the new or grow- 

 ing bone is often seen covered with granu- 

 lations. In cases of amputation, when the 

 bone protrudes after eight or ten days, the cut 

 extremity is observed to be fungoid and granu- 

 lated. And in some cases of compound frac- 

 ture we can observe the process of granulation 

 going forward, and actually see that it is thus 

 the union is completed. It nevertheless ap- 

 pears very doubtful whether granulation has 

 any part in the process of uniting a fracture, 

 unless where a communication exists between 

 the broken ends of the fragments and the ex- 

 ternal air. In a compound fracture, or in the 

 case of a bone protruding from a stump, there 

 will be granulations, often to a degree of 

 excessive exuberance; and in them there will 

 be a deposit of osseous substance, because 

 new structures always assume to a certain 

 extent the nature of the parts from which they 

 are produced ; but in a case of simple fracture, 

 where there is no wound, no communication 

 with the atmosphere, and not a single drop 

 of purulent matter is formed, it is very doubt- 

 ful whether granulations could exist; at least 

 their existence has never been demonstrated. 



Amongst modern pathologists, Meckel's* opi- 

 nion is entitled to very great respect, although 

 we may not be disposed to accede implicitly 

 to his views. He ranks among those who 

 consider the process of consolidation in frac- 

 ture to be similar to that of original ossi- 

 fication, and states, that at first there is an 

 effusion of a gelatinous substance which gra- 

 dually becomes firmer and more solid in con- 

 sistence, and is converted into cartilage, in the 

 interior of which osseous nuclei appear that 

 join to each other and to the broken ends of 

 the bone, and also envelope any fragments that 



* Manuel d'Anatomie, torn. i. p. 335. 



may have been detached. At the same time 

 the spiculae or scales become rounded off in 

 order that the surrounding parts may not suffer 

 injury or irritation. It is not necessary to the 

 perfection of this union that the ends of the 

 fragments should be accurately in contact: 

 it is sufficient if they lie against each other, 

 and then the union occurs by the same means, 

 and exactly on the principle of anchylosis 

 taking place between different bones. It must 

 be understood that this ossific deposit is laid 

 down both external to and within the bone ; 

 that when union is complete, the bone is di- 

 vided into two cavities internally ; and that, 

 for a length of time afterwards or for ever, 

 it may be known, by making a longitudinal 

 section, whether a bone had ever been broken 

 or not. He further states that the part sur- 

 rounded and joined by ossified callus is 

 stronger and firmer than any other, and to all 

 appearance this observation is correct, but it is 

 contrary to one of Mr. Howship's experiments, 

 who saw the callus break down and crumble 

 away in an attempt to calcine it, and therefore 

 concluded that it was softer and more highly 

 animalized. 



Hitherto we have noticed a number of the- 

 ories, all of which, with the exception of that 

 of Duhamel, bear a strong similarity to each 

 other, the principal points of difference being, 

 1. as to whether the soft gelatinous substance, 

 which all agree in having seen, was the fibrine 

 of the blood deprived of its colouring matter, 

 or genuine coagulating lymph effused by in- 

 flamed vessels : 2. whether this in process of 

 time was changed into real cartilage, or the 

 osseous deposition took place into this lymph 

 very much inspissated : and, 3. whether any- 

 thing like adhesion happened, or the conso- 

 lidation was perfected after the manner of 

 union by the second intention, namely, by 

 granulation. We now proceed to take a view 

 of a new theory bearing some resemblance to 

 that of Duhamel, and supported by the autho- 

 rity of Dupuytren. He supposes that there 

 are two distinct and different processes in the 

 union of bone. First, that there is a callus 

 formed like a brace or ferule round the frag- 

 ments externally, with a plug of the same 

 material within, the object of this provision 

 being, to hold the ends of the fracture in ap- 

 position whilst the union that is to be per- 

 manent is going forward : thus we are to 

 imagine a kind of natural splint placed around 

 and within the fractured pieces in order to 

 preserve them in situ. This preliminary pro- 

 cess commences almost immediately after the 

 accident, and is completed in the space of 

 from four to six weeks. Matters remain thus, 

 while the ends of the bones are becoming per- 

 manently united, which they are in about eight 

 months, during the latter period of which time 

 the mass of new material is declining in size, 

 and is eventually removed so as to leave the 

 bone of its natural extent and figure. The 

 formation of this first callus, which he calls 

 " cal provisoire," is attributed to the perios- 

 teum and occasionally to all the surrounding 

 structures, and in the centre of it he sup- 



