190 



PELVIS. 



of the weight of the bone) in 100 parts the 

 great diminution of the earthy matter will be 

 evident. 



In rickets the bones of the lower extremities 

 first exhibit deformity, which appears chiefly 

 as an aggravation of the natural curves under 

 pressure, and as a yielding in the direction of 

 the lines of muscular motion. The femurs, for 

 instance, are bent, in most cases, with the con- 

 vexity forwards and a little outwards ; the 

 tibiae and fibulae generally with the convexity 

 forwards and inwards, so that the knees are 

 bent inwards and the feet thrown outwards 

 and backwards (see Jig. 122. B and E.) The 

 bones of the pelvis and spine become affected, 

 and those of the upper extremities, ribs, and 

 head afterwards follow. 



The spinal column may be extensively 

 deformed, especially at its upper part, with- 

 out any deformity whatever of the pelvis. 

 An example of this is to be found in the 

 Museum of King's College, and many in the 

 Hunterian Museum. Many others are also 

 recorded. In most of these cases, however, 

 the special curvature results from caries of 

 the vertebra, or lateral curvature. 



Meckel remarks, that spinal curves result- 

 ing from general disease of the bones, such 

 as rickets, are usually accompanied by pel- 

 vic deformity. The lumbar portion of the 

 spine is curved forwards and sideways, the 

 thoracic portion backwards ; and sometimes, 

 the bodies of the vertebras become affected 

 with caries, and produce angular curvature 

 and ankylosis. The sacrum at the same 

 time sinks under the weight of the spine, and 

 the pelvis becomes impressed, generally, with 

 the complete ovate distortion, or one of the 

 partial deformities of brim, cavity, or outlet, 

 which are its commencements. In a good 

 many cases, however, as we shall presently see, 

 the rickety pelvis assumes the* angular form 

 of distortion ; ami, in some, the oblong form 

 previously described. It is, however, univer- 

 sally shallow, contracted, and of small ca- 

 pacity. The iliac wings are thin, and present 

 a greater central area of translucency than 

 usual ; while the columnar masses of bone 

 are shorter, lighter, and less dense, but often 

 present, as we have seen in the ovate pelvis 

 with universally diminished diameters, a 

 thickening of their bulk, corresponding to the 

 shortening they have experienced by pressure. 



Rokitansky mentions that this thickening 

 takes place in common with all the osseous 

 structures abounding in diploetic tissue. In 

 many instances, it evidently depends upon the 

 excess of reparative osseous deposit, described 

 by Stanley as taking place in the lines of the 

 greatest pressure. In all the specimens I 

 have examined, it takes place by far the most 

 considerably in the cotylo-sacral rib, through 

 which the greatest amount of pelvic pressure 

 passes. Shaw pointed out that in most rickety 

 deformed pelves, the contraction of the diame- 

 ter at the brim is universal as well as dispro- 

 portionate, from the absolute shortening and 

 atrophy of the bones. In fourteen rickety 

 k-nial adult pelves, he found a general de- 



ficiency, in the measurements of the bones, of 

 one quarter of the whole normal size, lie 

 also found that the bones of the lower ex- 

 tremity generally are atrophied in this disease 

 more than those of the upper.* Kokitansky 

 also considers rickets to interfere with the 

 general development of the bone. 



Mollifies osmium or Malacosteon adultorum 

 is a disease, not very frequent, affecting the 

 full-grown adult skeleton. It most commonly 

 affects the female sex about the middle period 

 of life, but seldom, according toRigby, attacks 

 women who have had no children. Three 

 instances in which this disease occurred in 

 the male subject are, however, given by Mr. 

 Curling in the Med. Chir. Trans, (vol. xx. 

 p. 360.). Nor does it seem to be confined to 

 middle age in Kellies' case, the woman was 

 aged only twenty-seven years nor to par- 

 turient women, as will be seen in Mr. Solly's 

 case. 



In many cases, it is said to depend upon the 

 cancerous diathesis, and to result from the 

 dissemination of cancerous matter throughout 

 the system, infecting the nutrition of the 

 animal matter of the bones, and replacing the 

 earthy constituents ; thus causing the osseous 

 structures to lose their cohesive power. By 

 far the greater proportion of the complete 

 cases of pelvic deformity, as well as the most 

 extreme and universal contraction of diame- 

 ters, have resulted from this disease. 



For the particular pathological instances of 

 this remarkable disease the reader is referred 

 again to the article on the Pathology of Bone 

 (p. 442. vol. i.) In addition to the cases 

 there described, may be mentioned one which 

 was brought before the Med. Chirurgical 

 Society by Mr. Solly, and published in 

 vol. xxiii. of the Transactions (p. 437.). The 

 subject was a female who had never borne 

 children, and the fragility of the bones ap- 

 peared at as early an age as twenty-two. 

 She had violent pains in the back, and a white 

 sediment in the urine. At the age of twenty- 

 four, the spine began to yield, and she had 

 rheumatic pains in the head. At thirty-six 

 years, the catamenia ceased, and the patient 

 began to be unable to walk or stand, and had 

 great pain ; the greatest deformity being then 

 apparent about the hips and shoulders. The 

 bones of the head then became thickened, and 

 those of the lower extremities more curved, 

 and fractured by the slightest force;': but 

 the urine at this time was clear and natural. 

 The patient died, worn out by the disease ; 

 and post-mortem examination showed the 

 long bones to be reduced to mere outer shells, 

 which could easily be cracked by pressure 

 with the finger and thumb. The interior was 

 filled with grumous matter, of hues varying 

 from dark blood to light liver-colour. Both 

 the femurs were broken, the tibias and fibula? 

 bent, the spine ranch curved, and the pelvis 

 extremely reduced in its diameters ; but the 

 joints and cartilages were all healthy. The 

 cranial bones were much thickened, and so 

 soft as to be easily cut with a knife. The 

 * Med. Chir. Trans, vol. xvii. p. 434. 



