202 



PELVIS. 



ankylosis of the right sacro-iliac joint, but no 

 atrophy of that side of the sacrum, though the 

 oblique deviation was present in a small degree, 

 the right innominate bone being a little more 

 elevated, contracted, and flattened than the 

 left. The whole appearance of this pelvis bore 

 somewhat a resemblance to that of an animal, 

 and presented on the posterior part of the ex- 

 ternal surface of each iliac wing a remarkable 

 protuberant growth of bone, as well as an 

 articulation by fibro-cartilage between the 

 left lateral mass of the sacrum and the trans- 

 verse process of the last lumbar vertebra, 

 which was unusually large.* This last peculi- 

 arity was also observed in an obliquely de- 

 formed female pelvis in which both the last 

 transverse processes were enlarged and bifur- 

 cated ; the right being articulated by fibro- 

 cartilage to the corresponding lateral mass of 

 the sacrum, and the left (the side on which 

 the sacro-iliac coalescence existed) similarly 

 articulated to the inner surface of the ilium 

 just above the sacro-iliac junction.-f* 



As a contrast to specimens like the two last, 

 Naegele mentions a well-built female pelvis, 

 in which the left lateral mass or side-piece of 

 the sacrum was, by arrest of development, di- 

 minished to the size and appearance of the 

 last lumbar transverse process, but presenting 

 an osseous protuberance, about the size of a 

 bean, as if of the aborted ossific centre, while 

 that on the right side was quite normal in size 

 and appearance.^ 



He had seen two others similarly deformed, 

 and mentioned examples in the collections of 

 Sebastian at Groningen, and Vrolik at Amster- 

 dam, and many more in the Pathological Mu- 

 seum at Paris, and others mentioned by Creve 

 and Retzius. Such irregularities of the sacrum 

 are not uncommonly found. 



A young female pelvis is described by Dr. 

 Knox as presenting an example of the ob- 

 liquely deformed pelvis in an earlier stage. 

 The right half of the sacrum is more than 

 half an inch narrower than the left, the first 

 piece not ossified to the second, and the cor- 

 responding half of the pelvic inlet proportion- 

 ably smaller, the pubic symphysis being oppo- 

 site the right sacral foramina; but the iliac 

 portion of the innominate bone is tolerably 

 symmetrical, and there is no sacro-iliac anky- 

 losis. The lumbar vertebrae present an ex- 

 tensive lateral curve. The same author also 

 mentions that in Dr. Campbell's Museum 

 there is a complete specimen of the obliquely 

 ovate pelvis, deformed on the left side, and 

 presenting a large exostosis on the last lumbar 

 vertebra. In his own possession hehas portions 

 of two other pelves, both exhibiting ankylosis of 

 the sacro-iliac joint on the left side, but in one 

 partial only, with twisting of the sacrum and 

 contraction of the ilium, such as would pro- 

 duce, if the specimens were entire, the oblique 



* Tafel xi. Das Schrag Verengte Beckon, 

 t Num. 10., tafel iii. Op. cit. 

 J Heidelberg Klin. Annal., vol. x. p. 4G8. 

 Med. Gazette, vol. xxxii. p. 537. 



deformity of M. Naegele. On looking over a 

 collection of human bones taken from an old 

 London graveyard, I have lately met with a 

 well-marked specimen of this disease on the 

 right side, in which there is a line or cicatrix 

 at the sacro-iliac point of coalescence. 



From the many specimens which had come 

 under his observation in so short a time, and 

 with but few opportunities of seeing them, 

 Naegele was led to conclude that this de- 

 formity occurred pretty frequently. 



Its influence upon parturition will present 

 an obstacle, not only to the forward progress 

 of the foetal head, but also to its proper rota- 

 tion, which will vary with the general extent 

 of the pelvic diameters. If the pelvis be of 

 large size, this deformity, though great, will 

 have less influence than in a smaller pelvis, 

 with a less degree of distortion. The foetal 

 head may enter the brim with its long diameter 

 in the long oblique diameter of the distorted 

 pelvis ; but when in the pelvic cavity it will 

 not be able to make the requisite turn into the 

 antero-posterior diameter of the outlet, and 

 will generally, in the opinion of Naegele, re- 

 quire the use of the forceps to extract it. 



The obstruction occurs in the first labours, 

 and its importance may be considered as equal 

 to those resulting from rickets and malacos- 

 teon, when it is considered, that in all the 

 cases of labour hitherto published, where this 

 deformity has been present, both mother and 

 child have been lost, although in the hands of 

 the most experienced accoucheurs. 



The diagnosis of the oblique distortion by 

 the usual measurements is very difficult. It is 

 rendered still more difficult by the absence of 

 any history or peculiar appearance of the 

 patient, indicative of the condition of the pel- 

 vis ; persons affected with it being usually, 

 in other respects, well built and healthy. 

 The diagnosis, moreover, is usually called 

 for in first labours. The promontory of the 

 sacrum is not to be felt by the finger, an usual 

 indication of plenty of room at the brim ; and 

 yet there may be sufficient contraction in the 

 oblique or sacro-cotyloid diameters, to require 

 the Caesarian section. The antero-posterior 

 diameter, which would show, if a section were 

 made in the centres of the sacral-promontory 

 and pubic symphysis, a clear space of 3 to 4? 

 inches, may appear, in the living subject, to 

 be contracted to!2i inches. The contraction 

 of this distortion is as totally unrecognisable by 

 the use of Baudelocque's calipers, which may 

 lead to gross error. 



The amount, in the well-formed female, of 

 the measurements instituted by Naegele for 

 the purpose of ascertaining the presence of 

 this deformity upon the living subject, have 

 been given in a former section of this article. 

 The results of the measurements of eight 

 female pelves obliquely deformed, in five of 

 which the ankylosed joint was that of the left 

 side, gave the following differences in measure- 

 ment between the two sides. 



