714 THE INDIAN MEDICAL GAZETTE [Dec., 1941

A METHOD FOR ASCERTAINING THE

OVERLAPPING OF THE PUBIS BY THE

HEAD BY MEANS OF ABDOMINAL

EXAMINATION ALONE*

By N. A. PURANDARE, m.d., f.c.p.s. (Bom.), f.r.c.o.g.

and

B. N. PURANDARE, m.d., f.r.c.s. (Edin.)

Antenatal supervision is now in general recognized as indispensable, and there is no

civilized country, where it is not practised. One of the essential objects gained by it is the

determination of the cephalo-pelvic relation soon enough to form beforehand a clear conception about the character and behaviour of the future labour. The cephalo-pelvic relation is made out by the engagement of the head. The latter can be determined by palpating the head at the

brim, to know how far it has descended into the pelvis. The other method for judging this relation

is by ascertaining the height of the anterior shoulder above the top of the symphysis pubis. By palpation of the head at the pelvic brim, we can find out how much of the head is to be felt above the pelvic cavity, whether it is

one-fourth, one-half or three-fourths, the rest of it at the same time being naturally in the cavity. When only one-fourth is felt above, the anterior shoulder is at the height of 2 inches from the pubis and the head has descended up to the ischial spines, and the greatest circum- ference of the head is in the pelvis. When half is made out above, the anterior shoulder is 3 inches from the pubis and the head has reached the mid-plane, and its greatest circumference is at the brim. When three-fourths of the head is

distinguished above the brim, the anterior shoulder measures 4 inches from the top of the pubis and the head is just entering the pelvis, the greatest circumference being naturally above the brim. When not entering the brim, the whole head is free above it and can be readily moved from side to side. The anterior shoulder is then from 4^- to 5 inches high. The head is, under the circumstances, also said to be

floating. When in this condition, it is to be seen whether it can be made to enter the pelvis.

In a multipara who has had several successive pregnancies, whose uterine wall as

well as abdominal wall might have lost its tone, and in whom the fcetal head might not have been pressed down into the brim, the head thus situated might be made to engage the pelvis by exerting pressure on it by both hands and

pushing it down towards the brim. Should it not enter, there is disproportion between the head and the pelvis; either the head may be

larger or the pelvis smaller than the average. As a rule, except when the head is exceptionally large, as in hydrocephalus, the large size of the

head in itself very seldom offers hindrance to its descent into the pelvis. This can be proved by the fact that the head is not infrequently delivered in the persistent occipito-posterior position even though its occipitofrontal diameter, measuring 4^ inches, is lying first across the pelvis and later in the antero-posterior diameter of the outlet. Usually in the normal occipito-anterior position, undergoing normal mechanism, the engaging diameter is sub- occipito-frontal, which is 3f inches and is

therefore f inch smaller, whereas with 4^ inches of the occipito-frontal diameter, the circum- ference of the head filling up the birth-canal is

comparatively very much larger; yet the

delivery is not uncommonly effected normally- This proves that moderate increase in size

of the head does not much matter, whereas diminution in the size of the pelvis does raise a material obstacle. Besides diminution in size of

the pelvis, other causes preventing the entrance ol

the_ head into the pelvis are placenta prsevia, obliquity of the uterus, feebleness of the uterine wall due to successive pregnancies at short in- tervals, great thickness of the extraperitoneal fat and of the abdominal wall, and development oj the placenta in connection with the anterior wall of the uterus; and also malpresentation of the child, such as face or brow presentation. E*"

cepting these conditions, .the head has more often than not entered the brim in due time- When the head has not gone down the bri&

and also it cannot be pushed into it, there might be disproportion. With this the head would be felt overlapping the symphysis pubis. This

overlapping may be slight, moderate or great. To ascertain whether the head can be made

to enter or not, and if not, how much it over-

laps the pubis, the method which is most

commonly used and gives the greatest help lS

the one advocated by Muller and Munro-Kerr- To carry out examination by this method? the patient is placed on her back in the

ordinary gynaecological position. Two fingelS are introduced into the vagina, while the thumb is made to rest on the top of the pubis. ^ assistant is then asked to make pressure on the

fundus, when the fingers in the vagina will note whether the head descends into the cavity ano to what extent. If it does not descend, th?

thumb above the pubis will perceive how mucJ1 it overlaps the pubis. But in this method as

the fingers are inserted in the vagina, there lS

every chance of conveying infection thei'e-

Secondly, an examiner with small hands ofte11 finds

_

it difficult to reach the top of the pubis> especially when the index and the middle finge1" are simultaneously in the vagina. To deal witB these conditions successfully a method ha

been devised. It gives almost precise informa- tion. We have both been practising it for som time now and have found it useful. It 1

carried out as follows.

The patient is first placed on the examination table in the dorsal position, to ascertain that tn

* Read at the Third Obstetric and Gynaecological Congress at Calcutta in April 1941.

Dec., 1941] DYSTOCIAS DUE TO ANOMALIES OF THE FCETUS : BARAR 715

head is floating. Then the patient is moved down so as to bring the buttocks over the edge ?f the table. The examiner now stands in front of the buttocks and with the fingers of his right hand locates the top of the symphysis pubis and rests them above it. The patient is then Put in the exaggerated lithotomy position, the thighs being separated and completely flexed on the abdomen (figure 1). Should the head be felt to descend through the brim, the fingers will Notice it, especially by feeling the surface of the head behind the vertical plane of the

Posterior or internal surface of the symphysis Pubis (figure 2). To facilitate the recognition

the descent of the head, the assistant may be asked to press on the fundus, when the lingers will perceive it going down (figure 1). If it does not enter the brim, it would be riding the

pubis. To judge how far it is overlapping the top of the pubis, the fingers are run up along the front sur-

face of the head.

By this means some

conception may be formed about the amount of prominence' of the head. Further, the fingers may be held stretched straight up on the head, the hand resting flat on the anterior surface of the symphysis pubis, as felt while the patient 'is lying on the back (figure 3). In this way the

fingers can perceive whether the surface of the head is behind the plane of the anterior surface of the symphysis or

forms a prominence projecting forward.

1 t"-~* -o ?

'

J?ng as the surface of the head lies behind the

{Concluded at foot of next column)

i

(Continued from 'previous column) vertical plane of the anterior surface of the pubis the overlapping is slight (figure 3). But when the prominence exceeds this limit and is felt to project beyond the anterior surface, the

overlapping is great (figure 4)/ Determination of this condition is of practical importance because, so long as the overlapping is slight, there is every probability of the head engaging the cavity by undergoing safe moulding. As the patient is placed with thighs flexed

on the abdomen, the abdominal muscles are

relaxed, and they allow of the head being readily felt. Furthermore, the pelvis, which, when a

person stands, becomes tilted downwards and forwards, has its inclination reduced, when she lies on her back and her thighs are bent on the abdomen, its brim thereby coming to look up- wards. With this the head is brought in a line with the middle of the pelvic brim, thus enabling it easily to occupy the inlet. This mode of examination possesses certain

advantages which are set forth below.

(1) The examination can be carried out

readily at the outdoor or consultation rooms

without much preparation of, or any incon- venience to, the patient.

(2) There is no need to introduce fingers into the vagina, thus creating no occasion to introduce sepsis.

(3) The examination can be done by this

way every week in the last month of pregnancy, when the head is floating.

(4) Even in a multipara it helps to ascertain whether the head can be made to enter the

brim. (5) In slight disproportion, if induction of

premature labour is contemplated, this method will indicate the time when it should be done.

(6) As .the hand is held flat on the symphysis pubis with the fingers pointing towards the

head, it can perceive more precisely the amount of overlapping, whether slight or excessive.

This information obtained is of practical im-

portance because, when it is slight, spontaneous delivery by the natural passages may be anti-

cipated, but when excessive, Csesarean section

at term is at once indicated.

BIBLIOGRAPHY

Ker$ J. M. (1937). Operative Obstetrics. William Wood and Co., Baltimore.

PurandakEjN. A. (1936). J. Obstet. and Gyn. Brit. Emp., 43, 101.

Idem (1937). Ibid., 44, 726, 1109. Idem (1938). Ibid., 45, 287. | !.

J01

Fig. 1. Fig. 1.

W'J

Fig. 2. Fig. 2.

&

Fig. 3. Fig. 3.

Fig. 4. Fig. 4.