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trunk. This traction is the more useful because it allows the head to accommodate itself to the shape of the brim, whilst the forceps applied to the advancing head does not allow its favorable configuration, as we have already explained above.

Martin has recommended turning in cases of asymmetry of the brim, in order to bring the occiput situated within the narrower into the wider portion of the inlet. We do not doubt that such a change of position may be attended with favorable results; we only wish to point out that in the asymmetrical rickety pelvis (of the ankylosed obliquely distorted pelvis we shall speak further on) the diagnosis of a moderate distortion is extremely difficult, and we must also leave it undecided whether the intended change of position can be obtained by turning. This indication has, at any rate, very little practical significance.

We therefore recommend version in all cases of pelvic contraction, where this is not absolute. Our reasons for doing so are-(1) in the interest of the mother; (2) in very great pelvic contraction with a conjugate diameter of 7 centimètres (2.8 inches) we have extracted live children; and 3rd, because perforation of the aftercoming head is neither more difficult nor more dangerous to the mother than that of the presenting head.

Occasionally we may have the pleasure of extracting a live child of moderate size through a conjugate which measures less than eight centimètres; at the worst it will only be necessary to perforate the aftercoming head; sometimes perforation is avoided, which would have been necessary had the head come first, by the spoon-shaped depression which diminishes the transverse diameter of the head. It is true that only half the number of children whose heads have been thus injured escape alive, but, seeing that perforation is an absolutely destructive operation. the results of that depression of the head are always more favorable.

As version has already been shown to give such good results in simple head presentations, the operation will, of course, be necessarily resorted to where dangerous complications exist. Where the forehead or face is placed upon the brim, or an extremity or the cord prolapsed, turning is, in fact, the only proper treatment. The operation is also indicated in the narrow pelvis, for the same complications as in the normal, but especially in transverse positions, and in dangers threatening the life of the mother or the child.

Pelvic positions in the narrow pelvis are, when medical assistance is at hand, neither unfavorable to the mother nor to the child.

The death of the fœtus in utero greatly alters the line of treatment to be adopted. When the head is still movable above the brim turning and extraction are more easy and less dangerous than perforation to the mother, because it is not known beforehand whether the natural forces will be able to expel the perforated head. But if the head is firmly fixed in the brim, and the labour is greatly protracted after the death of the child, perforation is always to be performed, for the pains have much less difficulty in pushing a perforated head through the pelvis than one whose bulk is not reduced; there is no good reason to abstain from the mutilation of the dead body of the fœtus if the mother can profit by it. The pains are allowed to effect the delivery of the perforated head, and

the cephalotribe is only made use of when it becomes desirable in the interest of the mother to terminate the labour.

In the generally contracted pelvis the results of the various operations are somewhat different. The extraction of the aftercoming head is more difficult, so that the child will less often be delivered alive by turning. The objections to the use of the forceps in that form of pelvic deformity are not the same as in the flat pelvis, but even here it will be very difficult to extract a child uninjured, especially if the contraction continues into the pelvic cavity. It is, therefore, advisable not to make too forcible attempts with the forceps, and if the child dies in the mean time to remove the instrument immediately and to perforate. As by perforation all the diameters of the head are diminished, it appears to be the operation in the highest degree applicable to the generally contracted pelvis.

If the conjugate measures less than 61 cm. (2.5 inches) there is no hope of delivering a living child per vias naturales. The Cæsarean section is then the sole means of delivery, and, the mother assenting, it will the more readily be performed, as craniotomy in such cases is by no means an operation entirely free from danger to her. In practice, as long as there is the possibility of another way of delivery, the Cæsarean section is very rarely permitted, and in the highest degrees of pelvic contraction it will, as a rule, be necessary to perform craniotomy whether the child be alive or dead. But there is certainly a limit to the pelvic deformity where craniotomy becomes a far more dangerous operation than the Cæsarean section, and where the latter is preferable, even when the foetus is dead. is exceedingly difficult to decide what is this limit. In Germany 5 cm. (2.1 inches) are, as a rule, taken as the extreme limit of craniotomy. The English bring the child through a flat pelvis the conjugate of which only measures 4 cm. (1.5 inch), and Barnes entertains the hope that it will be possible to extend the extreme limit of craniotomy to a conjugate of 23 cm. (1 inch). In such extreme cases it is well not to have a too high opinion of one's own skill, and unless there are the necessary instruments at hand it is preferable to perform the Cæsarean section, not only because it is easier, but because under these circumstances it is the least dangerous to the mother.

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Whilst speaking of the treatment of the narrow pelvis we have all the time supposed that the physician has been summoned to a case at the commencement of labour. But if he has an opportunity of detecting the deformity during pregnancy the induction of premature labour is then the treatment most beneficial to the mother, but less favorable to the child.

III.-The rarer Forms of Contracted Pelvis

A.-The Spondylolisthetic Pelvis

The spondylolisthetic pelvis is very rarely met with. Until now only eight such pelves have been the subject of obstetric observation; in seven of these this peculiar deformity has been ascertained by post-mortem examination and subsequent maceration. In the cases recorded by Hugenberger, Barnes, Lehmann, and Blake, the deformity was probably the same.

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The peculiarities of this kind of pelvis are the following:-The last lumbar vertebra slides down from the sacrum into the pelvis. The lower surface either partly projects into the pelvic cavity, or partly rests upon the upper surface of the sacrum, sometimes even its posterior surface lies upon the anterior

FIG. 18

surface of the sacrum. This change of position takes place gradually, so that the intervertebral cartilage atrophies and the shape of the corresponding lumbar vertebra is greatly modified by the friction with the sacral vertebræ. Frequently synostosis takes place between the two vertebræ, and the further sliding downwards is then arrested. By the descent of the lumbar vertebræ into the pelvis the conjugate diameter is more or less diminished. As the promontory for obstetric purposes is now replaced by the lumbar vertebræ, the conjugate will have to be measured between the symphysis and that part of the lumbar vertebræ which is nearest to the upper and inner margin of the symphysis. This was in three cases the lower margin of the fourth, in one the lower margin of the third or the upper margin of the fourth, and once even the lower margin of the second lumbar vertebræ. The degree of the contraction varies greatly. The antero-posterior diameter of the brim was, in the macerated pelves, 5, 51, 6, 7, 71, 74, twice 8, and 9 centimètres; the contraction was, therefore, as a rule, very considerable.

The contraction of the antero-posterior diameter of the brim is not, however, the sole change which the pelvis undergoes. Changes take place in it similar to those in the kyphotic pelvis. As the whole vertebral column-that is, the entire weight of the trunk-sinks into the pelvis, the centre of gravity would fall more forwards if this were not compensated by a diminished pelvic inclination, which, however, occurs quite constantly. The upper end of the sacrum is pressed backwards by the dislocated lumbar vertebræ, so that the base of the sacrum forces the posterior spines of the iliac bones asunder, and the apex of the sacrum projects more into the pelvis. The antero-posterior diameter of the outlet is somewhat contracted by this, whilst the proper conjugate-that is, the line between the symphysis and the first sacral vertebra-is enlarged. The transverse diameter gets gradually narrower towards the outlet, because the ischial tuberosities approach more closely on account of the separation of the iliac bones above, and of the traction of the ilio-femoral ligaments, which are greatly stretched through the diminished inclination of the pelvis. In some cases this contraction of the transverse diameter of the outlet was very considerable. As another consequence of the rotation of the sacrum, a greater mobility of the pelvic joints has been observed by Breslau.

The diagnosis is apparently easy on account of the great lordosis and the projection of the lumbar vertebræ into the small pelvis. If the last lumbar vertebra can be distinctly felt to join the sacrum at an angle, then, of course, there is no difficulty in recognising this kind of deformity; but if this is not the case it may be very difficult to

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distinguish between it and a rickety pelvis, for in rickets also there may be a high degree of lordosis, the last lumbar vertebra, which has descended into the pelvis, may be taken for the promontory, and its junction with the sacrum for a great curvature of the latter. Other rickety changes (in the clavicle, costal cartilage, and extremities) will, therefore, have to be looked for. There is a difference, also, between the two kinds of pelvis in the transverse diameters of the false pelvis. If the history also gives a negative result with regard to rickets, if no other rickety changes are visible, and if-as is the rule in the spondylolisthetic pelvis-the distance between the crests of the iliac bones is from 2 to 3 centimètres greater than that between the spines, it is absolutely certain that the pelvis is not a very deformed rickety one, for which alone it could have been mistaken.

Rickets being excluded in this way, there can scarcely be any doubt as to the existence of spondylolisthesis. Exostosis, just at that place, and of so regular a shape, would not occur simultaneously with so considerable a lordosis. If, moreover, the history shows that at an early period or immediately after puberty, there has been disease of the sacral region, the diagnosis of spondylolisthesis is certain; there is not always the peculiar waddling gait. On account of the descent of the vertebral column the place of division of the aorta is sometimes so low down that it, or at least both common iliac arteries, can be felt. Olshausen first called attention to it as a very important diagnostic sign, and Breslau in his second case could feel the aorta pulsating on the posterior wall of the pelvis. Hartmann was able to feel the place of division of the aorta as high up as the upper margin of the fourth lumbar vertebra.

The prognosis is very grave in all cases where the contraction is somewhat considerable, and certainly more unfavorable than in a rickety pelvis of the same degree of contraction; for in the spondylolisthetic pelvis the contraction is not limited to a short space, but it begins on account of the lordosis of the lumbar vertebræ already in the false pelvis, and does not cease when the narrow part has been passed, but continues into the pelvic cavity; besides, the outlet is also narrowed.

The treatment essentially depends upon the degree of contraction. On the whole it appears advisable to perform the Cæsarean section when the brim is greatly contracted.

Breslau's case, in which the conjugate measured 7 centimètres, is so far very instructive as the neglect of the Cæsarean section caused the death of the woman who was not delivered. In the cases of the Prague-Olshausen's and Belloc's pelvis the operation had been performed. The woman to whom the Paderborn pelvis belonged had heen operated upon twice, the first time with success. In the cases of Spaeth and Ender the child had been perforated. In Hartmann's case, where the diagonal conjugate measured 11 centimètres, premature labour had been twice successfully induced. Mature children, of course, would have been stillborn.

B.-The Kyphotic Pelvis.

The conditions requisite for the production of this form of pelvic deformity is that the kyphosis should be situated so low down that

its influence on the pelvis cannot be compensated by a lordosis still lower down. It is most characteristic when the kyphosis is situated in the lumbar vertebræ ; but kyphosis in the lumbo-sacral region also impresses upon the pelvis that peculiar shape even more markedly, only here the shape of the sacrum itself is altered. If the lower dorsal vertebræ are kyphotic the changes in the pelvis are still very distinct, though not quite so marked; but if the kyphosis is higher up in the dorsal vertebræ the characters of the pelvis are less defined, and from a considerable compensating lordosis of the lumbar vertebræ the pelvis may undergo changes of quite a different kind. It is only when the curvature is due to caries of the vertebral bodies that the changes are most characteristic of kyphosis, for that produced by rickets can only alter a pelvis which has already undergone rickety changes, and they are just the opposite to those of kyphosis. The most important changes in the pelvis observed in kyphosis occurring in the lumbar region are the following:

The upper portion of the sacrum is pressed backwards. The vertebral bodies project backwards from between their auricular surfaces, and the surface of the sacrum is greatly hollowed out from side to

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side. The anterior surface of the sacrum is also much elongated, and the promontory is very high up and far back. The longitudinal diameter is increased, the transverse diminished. The curvature from above downwards is only marked in the lower portion, the upper is often convex, and the whole anterior surface of the sacrum has an S-shaped curvature. On account of the rotation of the sacrum the antero-posterior diameter of the pelvic cavity, and still more so that of the outlet, is considerably smaller than the true conjugate.

The superior portions of the iliac bones are flat and transversely extended and their S-shaped curvature diminished. The distances between the spines and the crests of the iliac bones (and especially the former) are greater than the normal, whilst the posterior superior spines are more approximated on account of the smallness of the sacrum. The anterior inferior spines are remarkably developed, the lateral walls of the true pelvis are unusually high, and the iliopectineal line has a very straight course.

The ischial bones are very near to each other, and the distance between their tuberosities and spines is much less than normal. The pubic arch is consequently small, and its shape is very much like that of the osteomalacic pelvis.

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