818 



ABNORMAL CONDITIONS OF THE HIP-JOINT. 



on the head of the femur, which marked its 

 point of contact with the os innominatum : the 

 articulating surface thus formed on the head of 

 the femur was very slightly convex, about one 

 inch and a half in diameter, smooth, whitish, 

 hard, and polished, though not uniformly so ; 

 for in some parts the bone appeared red and 

 porous ; the remaining portion of the head of 

 the femur was not opposed to bone, but applied 

 to the capsule which surrounded the joint ; the 

 head had* lost its natural rounded form, was very 

 irregular, and deprived of its cartilage, but 

 some parts of it were covered by a substance 

 of the nature of ligament. There were several 

 small pits on the head of the femur, but none 

 of them appeared to have been the depression 

 for the attachment of the round ligament. 

 There was an irregular ossific deposit round 

 the lesser trochanter. 



The surface of the ilium, to which the head 

 of the bone was applied, was elevated half an 

 inch above the level of the surrounding bone, 

 so that this cavity appeared to have been formed 

 upon a plate of bone which had been planted, 

 as it were, on the ilium. The superior and 

 posterior portion of the new acetabulum, or 

 about two-thirds of its whole extent, was 

 smooth and polished, and presented a suitable 

 corresponding surface to receive the head of the 

 femur ; the aspect of the articulating surface on 

 the ilium was backwards, outwards, and up- 

 wards. There was scarcely a vestige of the old 

 acetabulum in its site ; there was a superficial 

 fossa, of a triangular form, filled with a fibrous 

 substance, continuous with a surrounding cel- 

 lular tissue. There was no articular cartilage 

 on any portion of the bones which formed the 

 new joint. There was a deep groove, one inch 

 in depth, formed on the outer side of the ilio- 

 pubic symphysis, for the lodgement of the con- 

 joined tendons of the psoas and iliacus muscles 

 in their passage over the brim of the pelvis to 

 the lesser trochanter. 



The pelvis, in this case, was much elevated 

 on the side corresponding to the luxation. 



b. Luxation backwards or towards the ischia- 

 tic notch. The space which is called the 

 ischiatic notch is bounded above and anteriorly 

 by the ilium, posteriorly by the sacrum, and in- 

 feriorly by the sacro-sciatic ligament (Jig. 323). 

 It is formed forgiving passage to the pyriformis 

 muscle and to the sciatic nerve, as well as to the 

 great arteries, the glutaeal, ischiatic, and internal 

 pudendal. Its situation, with respect to the 

 acetabulum in the natural position of the pelvis, 

 is a little above its level, and it is also placed 

 behind it ; when the head of the bone is thrown 

 into this space, it is placed backwards and up- 

 wards with respect to the acetabulum. Therefore 

 though called the dislocation backwards, it is 

 to be remembered that it is a dislocation back- 

 wards and a little upwards. 



In this dislocation the head of the thigh-bone 

 is placed on the pyriformis muscle, between the 

 edge of the bone which forms the upper part of 

 the ischiatic notch and the sacro-sciatic liga- 

 ments, behind the acetabulum, and a little above 

 the level of the middle of that cavity. 



Fig. 323. 



1, Pyriformis; 2, lesser sacro-sciatic ligament; 

 3, gemellus superior ; 4, obturator internus ; 5, ge- 

 mellus inferior ; 6, tuber ischii. 



It is the dislocation most difficult both to 

 detect and to reduce ; to detect, because the 

 length of the limb differs but little, and its po- 

 sition is not much changed as regards the knee 

 and foot, as in the dislocation upwards ; to re- 

 duce, because the head of the bone is placed 

 deep behind the acetabulum, and it therefore 

 requires to be lifted over its edge, as well as to 

 be drawn towards its socket. 



The signs of this dislocation are, that the 

 limb is about half an inch shorter than the 

 other, but generally not more than half an inch ; 

 that the trochanter major is behind its usual 

 place, but still remains nearly at right an- 

 gles with the ilium, with a slight inclination 

 towards the acetabulum ; the head of the bone 

 is so buried in the ischiatic notch that it cannot 

 be distinctly felt, except in thin persons, and 

 then only by rolling the thigh-bone forwards, 

 as far as the comparatively fixed state of the 

 limb will allow. The knee and the foot are 

 turned inwards, but not so much as in the dis- 

 location upwards, and the toe rests against the 

 ball of the great toe of the other foot. When 

 the patient is standing, the toe touches the 

 ground, but the heel does not quite reach it ; 

 the knee is not so much advanced as in the 

 dislocation on the dorsum ilii, but is still 

 brought a little more forwards than the other, 

 and is slightly bent. The limb is fixed, so that 

 flexion and rotation are in a great degree pre- 

 vented. 



The following case of dislocation backwards 

 towards the ischiatic notch affords us a good 

 example of this accident. John Magee, set. 54, 

 a strong muscular labourer, was admitted into 

 Jervis-street Infirmary, 10th of November, 1831, 

 under my care, in consequence of his having 

 been severely injured in his left hip. He stated 

 that while carrying on his back a sack of pota- 

 toes, (about 3 cwt.) he unfortunately placed his 



