AUNOU.MAI. CONDITIONS <>!' TIIK IIU'-JOINT. 



807 



Fig. 318. 



where the globular head joins the under part of 

 the neck, but which gradually enlarges down- 

 wards towards the lesser trochanter, and even 

 so low as the middle of the femur, where it 

 will be found nearly twice the breadth of the 

 opposite wall of the shaft of the bone ; the 

 compact stratum which, scarcely thicker than a 

 wafer, invests the entire of the head, upper part 

 of the neck, and trochanter, seems to have little 

 reference to any design of imparting strength or 

 resistance to this portion of the bone, and the 

 same may be said of the whole of the reticular 

 tissue of these processes, while, on the contrary, 

 the compact tissue of the under surface of the 

 neck seems artfully arranged, if we can so say, 

 so as to give sup|>ort to the weight of the body 

 in the erect position ; hence do we find this 

 compact stratum thrown into an arch, upon 

 winch the weight of the body falls, as that of a 

 carnage does on the C spring which sustains it. 



\\ iu>n we fall or leap from a height on the 

 feet or knees, the thin upper stratum of the 

 neck, and the whole of the reticular tissue of 

 the bone will first receive, and probably yield 

 somewhat to, the weight, by which some of the 

 force of the shock may be decomposed, but to 

 the bony arch of compact tissue, to which we 

 have alluded, must ultimately be referred any 

 violence which the neck of the femur can re- 

 ceive from any impulse transmitted from above. 



We seldom hear of a fracture of the neck of 

 the femur occurring to a healthy adult when he 

 falls with violence on his feet or knees, for the 

 weight of the superincumbent body is thrown 

 in the most favourable manner on the bony 

 arch of compact tissue before alluded to, which 

 from its density and form, and strength deriva- 

 ble from both, it is almost always able to 

 resist ; and even a fracture of the aceUibulum 



or rupture of the capxiUr ligament ami 

 cation are accidents more likely to hap|HMi 

 under these circumstances. 



But, on the other hand, let us suppose a 

 person to fall on the trochanter major, winch i< 

 I by the ground, while the weight of the 

 pelvis, &c. acting obliquelj on the under sur- 

 face of the neck, will have a tendency to brim 

 the neck of the femur into a straight line with 

 the shaft of the bone, or in other words, to 

 efface its obliquity ; here the compact tissue, so 

 often alluded to, receives the force from below 

 in a most unfavourable manner, and this tissue 

 cracks across, and if no more happens for the 

 present, we shall have the simplest form of 

 partial fracture of the neck of the femur. 



While circumstances are in this state, we 

 can conceive the possibility of a patient being 

 able to stand after such an accident, and even 

 walk for some distance; and when examined 

 by the surgeon, we can understand how the 

 latter, as it has often happened, might be de- 

 ceived into the opinion that there was really no 

 fracture. Again, we can easily imagine how 

 under such circumstances an awkward move- 

 ment or a fall may render the fracture complete, 

 or how, from a severe secondary injury, or even 

 the continued action of the first impulse, some- 

 what varied in its direction, the upper fragment 

 of the broken neck of the femur could be 

 wedged into the cancelli of the shaft. 



Anatomical character! of fracture of the 

 neck of the thigh-bone. In those cases in which 

 opportunities have occurred of making recent 

 anatomical examinations of those who have 

 died shortly after having suffered fracture of 

 the neck of the thigh-bone, blood has been 

 found extensively extravasated beneath the skin, 

 among the interstices of the muscles, and we 

 find the line of the fractures through the tro- 

 chanters and upper portion of the shaft of the 

 femur itself marked out by blood in a coagu- 

 lated state, which had insinuated itself into and 

 among the interstices of the broken bones. 

 When we examine a case of intra-capsular 

 fracture which had taken place a long time 

 previously to the death of the patient, very 

 remarkable changes in the structures around 

 the joint are noticed. The muscles, when com- 

 pared with those of the opposite side, are more 

 or less atrophied. This observation, however, 

 only applies to the greater number of the 

 muscles around the hip-joint, as some of the 

 smaller ones (in cases of ununited fractures of 

 the neck of the thigh-bone of long standing) 

 are usually found to have undergone a con- 

 siderable change in their appearance and struc- 

 ture ; of all these, the obturator externus seems 

 to be the most changed and thickened. Tins 

 is easily accounted for, when we recollect that 

 when the neck of the femur is fractured, there is 

 a strom; tendency in the muscles around the joint 

 to drag up the femur, and cause its shortening ; 

 indeed, the capsular luament and the obturator 

 externus alone resist the ascent of the head of 

 the bone on the pelvis. The tonic force of the 

 muscles has constantly this tendency to i-h \au 

 the femur on the dorsum of the ilium, and 

 when the patient begins to walk, and to throw 



