In one case, which was observed during life by the author himself, he observed a slight halt in the gait of the patient, who otherwise VMS apparently well-built, healthy, and active. In her first labour, at the age of eighteen years, the fcetal head in the early stage was found placed very high, and easily moveable, and the sacral promontory could not be reached by the finger. The patient was delivered, on the third day, with extreme difficulty by the aid of the forceps, and died fifteen days afterwards from puerperal fever. The pelvis was found affected with the oblique deformity, but in strength, weight, and texture perfectly healthy (fig. 123.). The sacrum was composed of four pieces only, and measured in length 2 inches 11 lines. The coccyx had six pieces, and measured 1 inch 10 lines. The left sacro-iliac joint was ankylosed, and the same side of the sacrum was shrunk and con tracted, so as to measure from the sacral pro montory to the usual position of tbe sacro iliac joint, only 1 inch 4 lines ; whereas the same measurement on the right side amounted to 2 inches 2 lines. The length of the left iliac crest was 3 lines less than that of the right. From the sacral promontory to the left superior anterior iliac spine measured only 3 inches 11 I lines. The same measure ment on the right ,ide amounted to 5 inches 4 lines. At the brim of the pelvis the mea surements were :— A direct line drawn forward from the sacral promontory cut the left pubis at the junc tion of its superior and inferior branches, an inch external to the centre of the pubic sym physis. In the pelvic cavity the measurements were : — The lowest oblique diameter in these pelves described by Naegele, was found in one in the Aluseum of the Hospital of St. Catherine at Milan, in which the left oblique diameter was 2 inches 10 lines only ; while the right was 4 inches 6 lines. In the same pelvis, the right sacro-cotyloid measured only 1 inch 8 lines ; and the left 3 inches 1 line. In one case, the left, and, in another, the right sacro-cotyloid diameter, was as low as 1 inch 6 lines. In one instance, the distance between the tip of the coccyx and the tuber ischii of the ankyloid side, was only 1 inch. The left side was the one most frequently affected by the ankylosis, but the right side was also found affected in many of the specimens, and, among others, in the pelvis of an Egyptian female mummy.
In addition to the foregoing, three female pelves are described by the same author, in which the oblique deformity was present, but the diminution of the diameters not so great as to produce any great obstacle to parturition.
One of these is in the Museum of St. Bar tholomew's Hospital, and is rather above the medium size. The right side of the sacrum is imperfectly developed. The left oblique dia meter is nearly 11 lines less than the right ; and the right sacro-cotyloid distance, 10i lines less than the left. A line drawn directly for ward from the sacral promontory cuts the right pubis 1 inch external to the centre of the sym physis ; and the distance from the sacral pro montory to the symphysis is 4 inches 10i lines. One of them, in Naegele's own collection has six instead of five sacral pieces.
In none of these three pelves, however, is there ankylosis of either of the sacro-iliac joints, although the imperfect development of one side of the sacrum is evident.
In a male pelvis, on the contrary, there was 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-eartilage 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 correspondino. 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.t 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.t He had seen two others similarly deformed, and mentioned exarnples 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 staoe. The right half of the sacrum is more tan 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 vertebrx 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 luinbar 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 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.