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Interlocking and collision in multiple pregnancies
INTERLOCKING
AND
COLLISION
IN MULTIPLE
PBZlc)#ANCIBS
Two Case Reports R. 0. XWANN, M.D., IOWA CITY, IOWA (Frona the Department
of
Obstetrics and Gynecology,
State
University
of
Iowa)
OLLISION
and interlocking of twins are extremely rare complications of pregnancy. In spite of their infrequency most textbooks of obstetrics make some reference to them. Most young practitioners when confronted with their first few multiple births will be overly concerned about the possibility of the babies becoming entangled or locked. The incidence of locked twins, as reported by von Braun of Vienna, is once in 90,000 deliveries or approximately once in 1,000 twin births. There are in general two divisions in which the cases can be classified.l* 2 Everyone is familiar with the chin-to-chin locking that occurs when the first twin presents by the breech and the second by the vertex. This division has been classified as locked twins while a second group has been called collision of twins. A number of variations can occur with collision. Examples are: (1) two heads trying to enter the pelvis simultaneously (such a case follows), (2) two breeches trying to enter the pelvis simultaneously, (3) the aftercoming head of the first twin in breech presentation being arrested against the trunk of the second twin in a transverse lie. English authors39 4 use a broader classification and classify locked twins and collision under one heading of “twin locking.” Collision of Twins
C multiple
M. H. was a 22-year-old primigravida at term on Aug. 7, 1953. The pregnancy progressed normally and on July 23, 1953, a clinical diagnosis of twins was made. X-ray pelvimetry on July 24 confirmed the diagnosis and showed normal pelvic measurements, One fetal skull was in midpelvis with the spine on the mother’s right side. The second fetal skull was in the right upper quadrant with the fetal spine on the mother’s left side. The patient went into labor at 1:00 P.M. on August 12. Both infants were in vertex presentation. Labor progressed slowly during the day and a sterile vaginal examination performed at 11:35 P.M. showed the cervix to be completely effaced and 3 cm. dilated. The first fetus presented as a vertex in a right occipitoposterior position and was at a plus 1 station. The membranes were ruptured artificially. Labor progressed slowly and the following morning the cervix was 4 cm. dilated with the head at a plus 2 station. It was evident that the patient had uterine inertia. She was started on antibiotics and was given intravenous dextrose (5 per cent) containing Pitocin at 1:00 P.M., August 13, after 24 hours of an inertial type of labor. The intravenous Pitocin was continued during the remainder of the day with fair results. A sterile vaginal examination at 11:30 P.M. that day showed the cervix to be 7 cm. dilated. The presenting part was at a plus 2 station and was in a right occipitoposterior position in a deflexed attitude. The patient was given morphine for sedation and rested well during the night. The following day she was again started on intravenous Pitocin. That evening she was again taken to the delivery room. The 907
908
SWANN
Am. J. Ok. & Gynec. April, 1957
presenting part, on vaginal examination, was just off the pelvic floor in a right oecipitoposterior position with the head slightly deflexed. The cervix was felt about the infant’s head and was described by the operator as being 9 cm. dilated. It was the operator’s opinion that vaginal delivery would offer greatest safety to both the mother and her infants. The use of Diihrssen’s incisions followed by low forceps delivery was contemplated. The fetal heart tones remained good. The patient was given a saddle block anesthesia and prepared for delivery. The cervix was easily pushed over the head making Diihrssen’s incisions unnecessary. Premature forceps were applied, a right mesiolateral episiotomy was performed, and the infant was delivered after three moderately hard tractive efforts. The infant did not make any effort to breathe and resuscitative efforts were unsuccessful. Immediately after the delivery of the first infant, the operator’s hand was inserted into the uterine cavity. The second twin was found to be presenting by the vertex. The head was pushed into the pelvis by fundal pressure, and the membranes were ruptured. The infant was delivered spontaneously within minutes and cried immediately. Examination of the first infant showed that the head, neck, and shoulders were discolored and edematous. The chest was flattened and concave. The lower portion of the infant appeared pale. A depression in the infant’s chest fitted almost perfectly a 10 to 12 em. sphere, the size of a normal fetal head. When such an object was placed in the cavity it was seen that the infant’s chin was pushed upward and the edema of its neck, which was mostly lateral, fitted closely around the edge of the object. It was known that during labor the head of the second infant was low and anterior in the midline. It was the impression of the operator that the difficulties of this labor and delivery could best be explained if it were presumed that the head of the second fetus lay over the chest of the first, whose back was lying directly posterior during labor and in the last days of gestation. During labor the infants came down as a unit, thereby producing an unrecognized dystocia. This probably also accounted for the uterine inertia and prolonged labor. The first infant was a small male and weighed 1,900 grams, while the second was also a male, weighing 2,965 grams. Both gross and microscopic examination of the placenta showed that they were double ovum twins. On autopsy there was an incomplete laceration of the tentorium cerebelli with extravasation of blood into the dura but no injury of major vascular channels was seen.
Locking
of Triplets
M. L. was a 23-year-old primigravida at term on March 24, 1955. On Jan. 22, 1955, it was suspected t.hat the patient was going to have twins. An x-ray of the abdomen At 12:30 A.M. the morning of February 4, the membranes showed the presence of triplets. ruptured spontaneously. On admission approximately one hour later, a sterile vaginal examination was performed to rule out any possibility of prolapsed cord. The presenting part was floating. The cervix admitted one finger and was 50 per cent effaced. A foot could be felt through the cervical OS but no cord was palpated. The patient was placed in bed and observed. On abdominal examination a head could be felt in the right lower quadrant of the abdomen. A second head was found in the left lower quadrant at a slightly higher level, and a third head was located in the right upper quadrant. At approximately 10:00 A.M., the patient went into spontaneous labor with the first baby preSeven and one-half senting as a complete breech in a right sacrotransverse position. hours later the cervix was completely dilated with the breech at a plus 2 station, With pudendal nerve block anesthesia, spontaneous delivery of the breech to the level of the umbilicus was permitted over a left mediolateral episiotomy. Assistance was given for the The anterior arm was delivered first. The infant’s delivery of the arms and shoulders. body was elevated and the posterior arm was delivered in the hollow of the sacrum. Some slight difficulty was encountered in performing this maneuver, which gave an impression that the aftercoming head was not readily entering the maternal pelvis. The operator’s left hand was inserted posterior to the baby, and it was found that the head of the second The second infant was presenting by the face, left mentum infant was entering the pelvis. The aftercoming head of the breech baby was locked above the head of the anterior.
Volume Number
73 4
INTERLOCKING
AND
COLLISION
IN
MULTIPLE
PREGNANCIES
$-@‘t
second infant. The patient was immediately given cyclopropane anesthesia. The head of the second infant was then pushed manually out of the pelvis thereby permitting the aftercoming head of the first infant to enter the pelvis and be delivered. The first infant was markedly asphyxiated but responded to resuscitation. The second infant again preIt was delivered by means of forceps and was only sented as a left mentum anterior. slightly asphyxiated. The third baby presented as a vertex in a left oecipitoanterior position and was delivered spontaneously. The first infant weighed 1,810 grams and was a male. The second infant was also a male and weighed 1,710 grams. The third infant, it The two male infants were identical as determined h!female, weighed 1,925 grams. examination of the placenta and later development. aI1 three infants survived an41 err apparently developing normally when seen and examined a year later.
Comment Interlocking and collision of twins usually cannot the onset of labor and are usually not detected until However, the operator should keep in mind the remote when labor is prolonged or does not pursue a normal pelvis should be of aid in making a diagnosis of collision
be predicted prior to the time of delivery. possibility of collision course. X-rays of the during labor.
The etiology of locking and collision has been ascribed to small babies, large pelvis, or a deficiency of amniotic fluid.l* 3 Lawrence,5 in 1949, reviewed 28 cases published since 1907 and found that 23 were in primigravidas and regarded this as a strong predisposing factor. The reason for this is not clearly understood. Of the 28 cases, 15 were chin-to-chin locking. In 9 patients both infants presented by the vertex. A transverse collision occurred in 3, and in one both infants presented by the breech. Lawrence reported an over-all fetal mortality rate of 39 per cent. The first fetus was lost in more than half the entire series. The locking variety apparently was most dangerous to the fetus, with 13 out of 15 being st,illborn. There were no maternal deaths in the 28 cases reviewed. Treatment is variable and depends upon the circumstances found in each locking, if the pelvis is large and the individual case. In true chin-to-chin babies are small, an attempt should be made to dislodge and disengage the heads.6 This can best be done if locking is recognized prior to the delivery of the arms and shoulders. The operator inserts his hand posterior to the neck Upward pressure is of the breech and grasps the head of the second twin. then applied to both the head of the second twin and the trunk of the first infant. As the head of the second twin is elevated, in favorable cases, it will be felt to slip past the aftercoming head of the breech baby. Gentle downward traction on the breech brings the aftercoming head into the pelvis so that dclivery can be executed. It is believed that deep general anesthesia is best for this maneuver; it not only insures a quiet patient, but it relaxes the uterus, permitting intrauterine manipulations with greater safety and less possibility of rupture of the lower uterine segment. Various authors have reported delivering the second twin by means of forceps, past the neck and body of the breech, if the heads are locked deep in
910
Am. J. Obst.
SWANN
& Gynec.
April.
1957
the pelvis. If the pelvis is large, it is possible in some cases to deliver the infants in a locked position using forceps on the second infant’s head as described above.? It may be necessary to decapitate the breech twin, disengage the heads, deliver the second twin, and then allow the severed head to be delivered spontaneously. True locking occurs only during the process of delivery and therefore cannot be treated by means of cesarean section if both infants are to survive. It is best handled by one of the above described methods. If a contraction ring develops, it might be necessary to perform a cesarean section, Such a case has been reported by Williamson.4 Cesarean section is the procedure of choice in collision diagnosed during labor. in the mission
I wish to express my appreciation preparation of this paper; to to report their case of collision.
to Dr. J. H. Randall Drs. W. C. Keettel
for his interest and William
and suggestions Goddard for per-
References 1. Eastman, N. J.: Williams Obstetrics, ed. 10, New York, 1950, Appleton-Century-Crofts, Inc., p. 627. 2. Lattuada, H. P.: Am. J. Surg. 81: 448, 1951. 3. Holland, E. L., and Bourne, A.: British Obstetric and Gynaecological Practice, delphia, 1955, F. A. Davis Company, pp. 644, 1038. 4. Williamson, J.: J. Obst. L Gynaec. Brit. Emp. 60: 421, 1953. 5. Lawrence, R. F.: J. Obst. & Gynaec. Brit. Emp. 56: 58, 1949. 6. Greenhill, J. P.: Principles and Practice of Obstetrics, ed. 10, Philadelphia, 1951, Saunders Company, p. 445. Aa6.J. OBST.& GYNEC.~~: 1167,195O. 7. Kimball, A. P., and Rand, P. R.:
Phila-
W. B.
AND
COLLISION
IN MULTIPLE
PBZlc)#ANCIBS
Two Case Reports R. 0. XWANN, M.D., IOWA CITY, IOWA (Frona the Department
of
Obstetrics and Gynecology,
State
University
of
Iowa)
OLLISION
and interlocking of twins are extremely rare complications of pregnancy. In spite of their infrequency most textbooks of obstetrics make some reference to them. Most young practitioners when confronted with their first few multiple births will be overly concerned about the possibility of the babies becoming entangled or locked. The incidence of locked twins, as reported by von Braun of Vienna, is once in 90,000 deliveries or approximately once in 1,000 twin births. There are in general two divisions in which the cases can be classified.l* 2 Everyone is familiar with the chin-to-chin locking that occurs when the first twin presents by the breech and the second by the vertex. This division has been classified as locked twins while a second group has been called collision of twins. A number of variations can occur with collision. Examples are: (1) two heads trying to enter the pelvis simultaneously (such a case follows), (2) two breeches trying to enter the pelvis simultaneously, (3) the aftercoming head of the first twin in breech presentation being arrested against the trunk of the second twin in a transverse lie. English authors39 4 use a broader classification and classify locked twins and collision under one heading of “twin locking.” Collision of Twins
C multiple
M. H. was a 22-year-old primigravida at term on Aug. 7, 1953. The pregnancy progressed normally and on July 23, 1953, a clinical diagnosis of twins was made. X-ray pelvimetry on July 24 confirmed the diagnosis and showed normal pelvic measurements, One fetal skull was in midpelvis with the spine on the mother’s right side. The second fetal skull was in the right upper quadrant with the fetal spine on the mother’s left side. The patient went into labor at 1:00 P.M. on August 12. Both infants were in vertex presentation. Labor progressed slowly during the day and a sterile vaginal examination performed at 11:35 P.M. showed the cervix to be completely effaced and 3 cm. dilated. The first fetus presented as a vertex in a right occipitoposterior position and was at a plus 1 station. The membranes were ruptured artificially. Labor progressed slowly and the following morning the cervix was 4 cm. dilated with the head at a plus 2 station. It was evident that the patient had uterine inertia. She was started on antibiotics and was given intravenous dextrose (5 per cent) containing Pitocin at 1:00 P.M., August 13, after 24 hours of an inertial type of labor. The intravenous Pitocin was continued during the remainder of the day with fair results. A sterile vaginal examination at 11:30 P.M. that day showed the cervix to be 7 cm. dilated. The presenting part was at a plus 2 station and was in a right occipitoposterior position in a deflexed attitude. The patient was given morphine for sedation and rested well during the night. The following day she was again started on intravenous Pitocin. That evening she was again taken to the delivery room. The 907
908
SWANN
Am. J. Ok. & Gynec. April, 1957
presenting part, on vaginal examination, was just off the pelvic floor in a right oecipitoposterior position with the head slightly deflexed. The cervix was felt about the infant’s head and was described by the operator as being 9 cm. dilated. It was the operator’s opinion that vaginal delivery would offer greatest safety to both the mother and her infants. The use of Diihrssen’s incisions followed by low forceps delivery was contemplated. The fetal heart tones remained good. The patient was given a saddle block anesthesia and prepared for delivery. The cervix was easily pushed over the head making Diihrssen’s incisions unnecessary. Premature forceps were applied, a right mesiolateral episiotomy was performed, and the infant was delivered after three moderately hard tractive efforts. The infant did not make any effort to breathe and resuscitative efforts were unsuccessful. Immediately after the delivery of the first infant, the operator’s hand was inserted into the uterine cavity. The second twin was found to be presenting by the vertex. The head was pushed into the pelvis by fundal pressure, and the membranes were ruptured. The infant was delivered spontaneously within minutes and cried immediately. Examination of the first infant showed that the head, neck, and shoulders were discolored and edematous. The chest was flattened and concave. The lower portion of the infant appeared pale. A depression in the infant’s chest fitted almost perfectly a 10 to 12 em. sphere, the size of a normal fetal head. When such an object was placed in the cavity it was seen that the infant’s chin was pushed upward and the edema of its neck, which was mostly lateral, fitted closely around the edge of the object. It was known that during labor the head of the second infant was low and anterior in the midline. It was the impression of the operator that the difficulties of this labor and delivery could best be explained if it were presumed that the head of the second fetus lay over the chest of the first, whose back was lying directly posterior during labor and in the last days of gestation. During labor the infants came down as a unit, thereby producing an unrecognized dystocia. This probably also accounted for the uterine inertia and prolonged labor. The first infant was a small male and weighed 1,900 grams, while the second was also a male, weighing 2,965 grams. Both gross and microscopic examination of the placenta showed that they were double ovum twins. On autopsy there was an incomplete laceration of the tentorium cerebelli with extravasation of blood into the dura but no injury of major vascular channels was seen.
Locking
of Triplets
M. L. was a 23-year-old primigravida at term on March 24, 1955. On Jan. 22, 1955, it was suspected t.hat the patient was going to have twins. An x-ray of the abdomen At 12:30 A.M. the morning of February 4, the membranes showed the presence of triplets. ruptured spontaneously. On admission approximately one hour later, a sterile vaginal examination was performed to rule out any possibility of prolapsed cord. The presenting part was floating. The cervix admitted one finger and was 50 per cent effaced. A foot could be felt through the cervical OS but no cord was palpated. The patient was placed in bed and observed. On abdominal examination a head could be felt in the right lower quadrant of the abdomen. A second head was found in the left lower quadrant at a slightly higher level, and a third head was located in the right upper quadrant. At approximately 10:00 A.M., the patient went into spontaneous labor with the first baby preSeven and one-half senting as a complete breech in a right sacrotransverse position. hours later the cervix was completely dilated with the breech at a plus 2 station, With pudendal nerve block anesthesia, spontaneous delivery of the breech to the level of the umbilicus was permitted over a left mediolateral episiotomy. Assistance was given for the The anterior arm was delivered first. The infant’s delivery of the arms and shoulders. body was elevated and the posterior arm was delivered in the hollow of the sacrum. Some slight difficulty was encountered in performing this maneuver, which gave an impression that the aftercoming head was not readily entering the maternal pelvis. The operator’s left hand was inserted posterior to the baby, and it was found that the head of the second The second infant was presenting by the face, left mentum infant was entering the pelvis. The aftercoming head of the breech baby was locked above the head of the anterior.
Volume Number
73 4
INTERLOCKING
AND
COLLISION
IN
MULTIPLE
PREGNANCIES
$-@‘t
second infant. The patient was immediately given cyclopropane anesthesia. The head of the second infant was then pushed manually out of the pelvis thereby permitting the aftercoming head of the first infant to enter the pelvis and be delivered. The first infant was markedly asphyxiated but responded to resuscitation. The second infant again preIt was delivered by means of forceps and was only sented as a left mentum anterior. slightly asphyxiated. The third baby presented as a vertex in a left oecipitoanterior position and was delivered spontaneously. The first infant weighed 1,810 grams and was a male. The second infant was also a male and weighed 1,710 grams. The third infant, it The two male infants were identical as determined h!female, weighed 1,925 grams. examination of the placenta and later development. aI1 three infants survived an41 err apparently developing normally when seen and examined a year later.
Comment Interlocking and collision of twins usually cannot the onset of labor and are usually not detected until However, the operator should keep in mind the remote when labor is prolonged or does not pursue a normal pelvis should be of aid in making a diagnosis of collision
be predicted prior to the time of delivery. possibility of collision course. X-rays of the during labor.
The etiology of locking and collision has been ascribed to small babies, large pelvis, or a deficiency of amniotic fluid.l* 3 Lawrence,5 in 1949, reviewed 28 cases published since 1907 and found that 23 were in primigravidas and regarded this as a strong predisposing factor. The reason for this is not clearly understood. Of the 28 cases, 15 were chin-to-chin locking. In 9 patients both infants presented by the vertex. A transverse collision occurred in 3, and in one both infants presented by the breech. Lawrence reported an over-all fetal mortality rate of 39 per cent. The first fetus was lost in more than half the entire series. The locking variety apparently was most dangerous to the fetus, with 13 out of 15 being st,illborn. There were no maternal deaths in the 28 cases reviewed. Treatment is variable and depends upon the circumstances found in each locking, if the pelvis is large and the individual case. In true chin-to-chin babies are small, an attempt should be made to dislodge and disengage the heads.6 This can best be done if locking is recognized prior to the delivery of the arms and shoulders. The operator inserts his hand posterior to the neck Upward pressure is of the breech and grasps the head of the second twin. then applied to both the head of the second twin and the trunk of the first infant. As the head of the second twin is elevated, in favorable cases, it will be felt to slip past the aftercoming head of the breech baby. Gentle downward traction on the breech brings the aftercoming head into the pelvis so that dclivery can be executed. It is believed that deep general anesthesia is best for this maneuver; it not only insures a quiet patient, but it relaxes the uterus, permitting intrauterine manipulations with greater safety and less possibility of rupture of the lower uterine segment. Various authors have reported delivering the second twin by means of forceps, past the neck and body of the breech, if the heads are locked deep in
910
Am. J. Obst.
SWANN
& Gynec.
April.
1957
the pelvis. If the pelvis is large, it is possible in some cases to deliver the infants in a locked position using forceps on the second infant’s head as described above.? It may be necessary to decapitate the breech twin, disengage the heads, deliver the second twin, and then allow the severed head to be delivered spontaneously. True locking occurs only during the process of delivery and therefore cannot be treated by means of cesarean section if both infants are to survive. It is best handled by one of the above described methods. If a contraction ring develops, it might be necessary to perform a cesarean section, Such a case has been reported by Williamson.4 Cesarean section is the procedure of choice in collision diagnosed during labor. in the mission
I wish to express my appreciation preparation of this paper; to to report their case of collision.
to Dr. J. H. Randall Drs. W. C. Keettel
for his interest and William
and suggestions Goddard for per-
References 1. Eastman, N. J.: Williams Obstetrics, ed. 10, New York, 1950, Appleton-Century-Crofts, Inc., p. 627. 2. Lattuada, H. P.: Am. J. Surg. 81: 448, 1951. 3. Holland, E. L., and Bourne, A.: British Obstetric and Gynaecological Practice, delphia, 1955, F. A. Davis Company, pp. 644, 1038. 4. Williamson, J.: J. Obst. L Gynaec. Brit. Emp. 60: 421, 1953. 5. Lawrence, R. F.: J. Obst. & Gynaec. Brit. Emp. 56: 58, 1949. 6. Greenhill, J. P.: Principles and Practice of Obstetrics, ed. 10, Philadelphia, 1951, Saunders Company, p. 445. Aa6.J. OBST.& GYNEC.~~: 1167,195O. 7. Kimball, A. P., and Rand, P. R.:
Phila-
W. B.