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A New Measurement (Clinical) for Estimating the Depth of the True Pelvis
SCHUMAN :
497
PELVIC MEASUREMENTS
top of the symphysis (Fig. 18 A and B). Occasionally, however, this line strikes below the top of the symphysis (Fig. 18 C). In these cases (8 per cent) a markedly curved horizontal sacrum with wedging of the fifth lumbar vertebra is always present (Fig. 18 C). In one case, not in this series, spondolithiasis had occurred. The obstetric significance is not clear. The lumbosacral region becomes unstable mechanically and this entity may explain the severe lumbosacral pain noted occasionally i11 the postpartum period. REFERENCES
(1) Caldwell, W. E., amd Maloy, H. C.: AM. J. OssT. & GYNEC. 26: 479, 1933. (2) Molay, H. C.: Am. J. Roentgenol. 30: 111, 1933. (3) Jarrcho, Julius: The Pelvis in Obstetrics, New York, Paul B. Roeber, Inc. (4) Williams, J. W.: Obstetrics, New York, 1930, D. Appleton & Company.
_\NEW MEASUREMENT (CLINICAL) FOR ESTIMATING THE DEPTH OF THE TRUE PELVIS (PRELIMINARY COMMUNICATION) WILLIAM ScHUMAN,
M.D.,
BALTIMORE,
Mo.
(From the Obstetric Department of the Sinai Hospital, Baltimore) 0
x~:~:::d::~bl!~e:~~~f ~~~t;l:~o~~:::~ypr::~;n:~:a:::·::~~:~~:~: 1
fact that the information obtained is of extremely questionable value, so far as the obstetric prognosis is concerned. Without attempting to minimize the valuable contributions of Baudelocque, Michaelis, and others, it is beginning to appear that the intercristal and interspinous diameters, and even the external conjugate, will soon be relegated to their place in classical obstetric lore. Pioneers in the newer methods of x-ray pelvimetry are now making _clear their feeling with regard to orthodox pelvimetry. De Lee, in his textbook, states "the external ones (dimensions) are unreliable indices of the size of the pelvic cavity," and cites, as examples, pelves in his possession where the external conjugate is entirely misleading compared with the length of the true conjugate. The old classification of pelves is becoming less and less useful for clinical purposes, and the time has come when a more practical and rational classification will be necessary. To my mind, the greatest contribution to the study of the pelvis since Litzmann 's classification in 1861, and rivalling the studies of Breus and Kolisko of this century, is the recent work of Caldwell and Moloy resulting in a suggested classification on a morphologic basis. No obstetrician can afford to neglect to familiarize himself with that important piece of research on the female pelvis, for I feel that their work will mark a definite milestone in ob-
498
AMEHlCAN JOURNAL OF OBSTETRICS AND GYNECOLOGY
stetric progress. It is not intended here to review their work; suffice it to say that the idea embodied in this communication was directly inspired by their paper. My interest in the new classification began immediately upon reading the article. Here, apparently, was something that was going to clear up the haze surrounding· that large group of pelves, to all intents and purposes clinically normal, yet which prove obstetrically to be the very antithesis of normality. The android and anthropoid types of pelves, so called by Caldwell and Moloy, which today constitute, in this country at least, a large proportion of our female pelves, are certainly responsible for the many unanticipated dystocias-poor engagement, occiput posterior, transverse arrest, etc., that are experienced in everyone's practice. The male or funnel pelvis, whether or not associated with the D.D.S. type of individual, and the high assimilation pelvis have long
Fig. 1.-A diagram to show increased depth to the true pelvis. l:<~rom this it ean be seen that a deep (male) pelvis can be associated with a normal intertuberous diameter. (From Caldwell and .Moloy.)
been recognized as a real or potential cause for dystocia. The criteria for such a diagnosis, however, have not been very reliable. Usually a narrow pubic arch, a diminished intertuberous diameter, sharp or prominent ischial spines, decreased anterior or posterior sagittal diameter, singly or together, correctly or not, have given us the key to the condition. The chief, and clinically the most important, characteristic of the male, funnel, or high assimilation pelvis, namely, its increa.~ed depth, has been left to guesswork, without a means of obtaining an accurate estimate by clinical methods. "The promontory seems high" or "the symphysis is high'' represent the degree of accuracy to which we could attain in this important detail. Even x-ray pelvimetry, which has stressed the various diameters of the inlet, offers at present no measurement of pelvic depth.
SCHUMAN;
PELVIC' MEASllREMENTS
499
The purpose of this paper is to call attention to the use of a new external measurement, based on the suggestions of Caldwell and Moloy, and intended to estimate the depth of the true pelvis. These authors recall the observation by Hart, who identified the ''ischiopubic'' type, which refers to the male characters in the fore pelvis, and the ''iliasacral,'' which refers to those features in the posterior portion of the pelvis. Inasmuch as the anterior portion of the pelvis contains the most frequent and distinctive features found in the male or android type (for example, the triangular form of the inlet, narrow pubic arch, long pubic rami, etc.), it is logical to seek a measurement in the fore pelvis, which 'vill give us an index to the most constant of the male characteristics,
Fig. 2.-Method of measuring "pubotuberous" distance, giving depth of true pelvis. By means of the ordinary pelvimeter, it Is clinically possible to detect an increase in th•' normal distance between the upper border of the superior ramus of the pubis lilionectineal line) and the innPr border of the inferior surface of the ischial tuberosity. -:Both sides may be measured.
that is, increased depth, and which is readily obtainable clinically. The suggestion as to the measurement best suited for this purpose was inspired by the reference in the much-mentioned article to Todd's skeletal material at the Western Reserve University. Todd measured the perpendicular distance from the tuberosity of the ischium to the iliopectineal line in 53 white male and 50 white female pelves and found that for males this perpendicular averaged 101 mm. as compared with 90 mm. in the female. With the above figures in mind, I began to take this measure.tuent on women at every opportunity. This distance is easily measured by using
500
AMERICAN JOURNAl, OF OBSTETRICS AND GYNECOLOGY
the ordinary pelvimeter. It is best taken immediately after the intertuberous diameter has been measured, and with one end of the pelvimeter still on the tuberosity, the other end is swung around until at a point on the upper border of the superior ramus of the pubis directly perpendicular to the tuberosity. One or both sides may be measured. l have found this distance to average 11.5 em. Allowance must be made for pubic and gluteal fat; in the patient of normal build, 1 ern. should be allowed for soft parts, and in obese patients, 2 ern. Therefore, for the average patient, in whom you obtain a measurement of 11 em., the true bony perpendicular will be 10. F'or the present, I shall call this diameter the "pubo tuberous" (right or left). A few interesting cases where the measurement has been applied will serve to show its value. An eighteen-year-old girl, whose average weight is 89 pounds, recently deliven•d without difficulty a baby weighing nearly 9 pounds. Her external conjugate is 17 em. On her regular postdelivery visit, I took her pubo tuberous measurement, and found it to be only 9.5 em., indicating a very shallow pelvis, conducive to an easy labor. Recently, a para iv entered the obstetric clinic of the Sinai Hospital with an early pregnancy. Her first two labors ended in stillbirths, the third by elective cesarean section with good results. External measurements were all normal, on internal examination th<' sacrum and promontory were not felt. I measured her puho tuberous perpendicular, and found it to bo 14 em. Allowing 2 em. for moderate obesity, the depth of her fore prlvis mea~nred 12 em., which would make it fall in the male, funnel, or high assimilation (android or anthropoid) class. Her outlet as determined by the T.I. (9.0 em.) was apparently not c•ontracted. Her pubic rami were obviously long, masking an acute subpubic angle.
Inasmuch as only a few determinations have been made on prenatal patients, it is too early to report the value of this measurement in prognosticating· dystocia. In our clinic, this dimension has just been added to the routine pelvic measurements, and after a sufficient number have been taken and correlated with labor records of these patients, a complete report will be made. Before that time, I trust others will begin the routine use of it, so that enough clinical data can be obtained soon to enable us to judge its usefulness. REFERENCE
Caldwell, W. E., aend Maloy, H. C.:
2340
EUTAW Pr,ACE
AM. J.
0BST. & GYNEC.
26: 479, 1933.
497
PELVIC MEASUREMENTS
top of the symphysis (Fig. 18 A and B). Occasionally, however, this line strikes below the top of the symphysis (Fig. 18 C). In these cases (8 per cent) a markedly curved horizontal sacrum with wedging of the fifth lumbar vertebra is always present (Fig. 18 C). In one case, not in this series, spondolithiasis had occurred. The obstetric significance is not clear. The lumbosacral region becomes unstable mechanically and this entity may explain the severe lumbosacral pain noted occasionally i11 the postpartum period. REFERENCES
(1) Caldwell, W. E., amd Maloy, H. C.: AM. J. OssT. & GYNEC. 26: 479, 1933. (2) Molay, H. C.: Am. J. Roentgenol. 30: 111, 1933. (3) Jarrcho, Julius: The Pelvis in Obstetrics, New York, Paul B. Roeber, Inc. (4) Williams, J. W.: Obstetrics, New York, 1930, D. Appleton & Company.
_\NEW MEASUREMENT (CLINICAL) FOR ESTIMATING THE DEPTH OF THE TRUE PELVIS (PRELIMINARY COMMUNICATION) WILLIAM ScHUMAN,
M.D.,
BALTIMORE,
Mo.
(From the Obstetric Department of the Sinai Hospital, Baltimore) 0
x~:~:::d::~bl!~e:~~~f ~~~t;l:~o~~:::~ypr::~;n:~:a:::·::~~:~~:~: 1
fact that the information obtained is of extremely questionable value, so far as the obstetric prognosis is concerned. Without attempting to minimize the valuable contributions of Baudelocque, Michaelis, and others, it is beginning to appear that the intercristal and interspinous diameters, and even the external conjugate, will soon be relegated to their place in classical obstetric lore. Pioneers in the newer methods of x-ray pelvimetry are now making _clear their feeling with regard to orthodox pelvimetry. De Lee, in his textbook, states "the external ones (dimensions) are unreliable indices of the size of the pelvic cavity," and cites, as examples, pelves in his possession where the external conjugate is entirely misleading compared with the length of the true conjugate. The old classification of pelves is becoming less and less useful for clinical purposes, and the time has come when a more practical and rational classification will be necessary. To my mind, the greatest contribution to the study of the pelvis since Litzmann 's classification in 1861, and rivalling the studies of Breus and Kolisko of this century, is the recent work of Caldwell and Moloy resulting in a suggested classification on a morphologic basis. No obstetrician can afford to neglect to familiarize himself with that important piece of research on the female pelvis, for I feel that their work will mark a definite milestone in ob-
498
AMEHlCAN JOURNAL OF OBSTETRICS AND GYNECOLOGY
stetric progress. It is not intended here to review their work; suffice it to say that the idea embodied in this communication was directly inspired by their paper. My interest in the new classification began immediately upon reading the article. Here, apparently, was something that was going to clear up the haze surrounding· that large group of pelves, to all intents and purposes clinically normal, yet which prove obstetrically to be the very antithesis of normality. The android and anthropoid types of pelves, so called by Caldwell and Moloy, which today constitute, in this country at least, a large proportion of our female pelves, are certainly responsible for the many unanticipated dystocias-poor engagement, occiput posterior, transverse arrest, etc., that are experienced in everyone's practice. The male or funnel pelvis, whether or not associated with the D.D.S. type of individual, and the high assimilation pelvis have long
Fig. 1.-A diagram to show increased depth to the true pelvis. l:<~rom this it ean be seen that a deep (male) pelvis can be associated with a normal intertuberous diameter. (From Caldwell and .Moloy.)
been recognized as a real or potential cause for dystocia. The criteria for such a diagnosis, however, have not been very reliable. Usually a narrow pubic arch, a diminished intertuberous diameter, sharp or prominent ischial spines, decreased anterior or posterior sagittal diameter, singly or together, correctly or not, have given us the key to the condition. The chief, and clinically the most important, characteristic of the male, funnel, or high assimilation pelvis, namely, its increa.~ed depth, has been left to guesswork, without a means of obtaining an accurate estimate by clinical methods. "The promontory seems high" or "the symphysis is high'' represent the degree of accuracy to which we could attain in this important detail. Even x-ray pelvimetry, which has stressed the various diameters of the inlet, offers at present no measurement of pelvic depth.
SCHUMAN;
PELVIC' MEASllREMENTS
499
The purpose of this paper is to call attention to the use of a new external measurement, based on the suggestions of Caldwell and Moloy, and intended to estimate the depth of the true pelvis. These authors recall the observation by Hart, who identified the ''ischiopubic'' type, which refers to the male characters in the fore pelvis, and the ''iliasacral,'' which refers to those features in the posterior portion of the pelvis. Inasmuch as the anterior portion of the pelvis contains the most frequent and distinctive features found in the male or android type (for example, the triangular form of the inlet, narrow pubic arch, long pubic rami, etc.), it is logical to seek a measurement in the fore pelvis, which 'vill give us an index to the most constant of the male characteristics,
Fig. 2.-Method of measuring "pubotuberous" distance, giving depth of true pelvis. By means of the ordinary pelvimeter, it Is clinically possible to detect an increase in th•' normal distance between the upper border of the superior ramus of the pubis lilionectineal line) and the innPr border of the inferior surface of the ischial tuberosity. -:Both sides may be measured.
that is, increased depth, and which is readily obtainable clinically. The suggestion as to the measurement best suited for this purpose was inspired by the reference in the much-mentioned article to Todd's skeletal material at the Western Reserve University. Todd measured the perpendicular distance from the tuberosity of the ischium to the iliopectineal line in 53 white male and 50 white female pelves and found that for males this perpendicular averaged 101 mm. as compared with 90 mm. in the female. With the above figures in mind, I began to take this measure.tuent on women at every opportunity. This distance is easily measured by using
500
AMERICAN JOURNAl, OF OBSTETRICS AND GYNECOLOGY
the ordinary pelvimeter. It is best taken immediately after the intertuberous diameter has been measured, and with one end of the pelvimeter still on the tuberosity, the other end is swung around until at a point on the upper border of the superior ramus of the pubis directly perpendicular to the tuberosity. One or both sides may be measured. l have found this distance to average 11.5 em. Allowance must be made for pubic and gluteal fat; in the patient of normal build, 1 ern. should be allowed for soft parts, and in obese patients, 2 ern. Therefore, for the average patient, in whom you obtain a measurement of 11 em., the true bony perpendicular will be 10. F'or the present, I shall call this diameter the "pubo tuberous" (right or left). A few interesting cases where the measurement has been applied will serve to show its value. An eighteen-year-old girl, whose average weight is 89 pounds, recently deliven•d without difficulty a baby weighing nearly 9 pounds. Her external conjugate is 17 em. On her regular postdelivery visit, I took her pubo tuberous measurement, and found it to be only 9.5 em., indicating a very shallow pelvis, conducive to an easy labor. Recently, a para iv entered the obstetric clinic of the Sinai Hospital with an early pregnancy. Her first two labors ended in stillbirths, the third by elective cesarean section with good results. External measurements were all normal, on internal examination th<' sacrum and promontory were not felt. I measured her puho tuberous perpendicular, and found it to bo 14 em. Allowing 2 em. for moderate obesity, the depth of her fore prlvis mea~nred 12 em., which would make it fall in the male, funnel, or high assimilation (android or anthropoid) class. Her outlet as determined by the T.I. (9.0 em.) was apparently not c•ontracted. Her pubic rami were obviously long, masking an acute subpubic angle.
Inasmuch as only a few determinations have been made on prenatal patients, it is too early to report the value of this measurement in prognosticating· dystocia. In our clinic, this dimension has just been added to the routine pelvic measurements, and after a sufficient number have been taken and correlated with labor records of these patients, a complete report will be made. Before that time, I trust others will begin the routine use of it, so that enough clinical data can be obtained soon to enable us to judge its usefulness. REFERENCE
Caldwell, W. E., aend Maloy, H. C.:
2340
EUTAW Pr,ACE
AM. J.
0BST. & GYNEC.
26: 479, 1933.