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tell an untruth; pretend with intent to deceive; "Dont lie to your parents"; "She lied when she told me she was only 29"
a statement that deviates from or perverts the truth (同)prevarication
position or manner in which something is situated
have a place in relation to something else; "The fate of Bosnia lies in the hands of the West"; "The responsibility rests with the Allies" (同)rest
be and remain in a particular state or condition; "lie dormant"
be located or situated somewhere; occupy a certain position
be lying, be prostrate; be in a horizontal position; "The sick man lay in bed all day"; "the books are lying on the shelf"
a German art song of the 19th century for voice and piano
Norwegian diplomat who was the first Secretary General of the United Nations (1896-1968) (同)Trygve Lie, Trygve Halvden Lie
Chinese distance measure; approximately 0.5 kilometers

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(幾何で)横断線
《場所を表す副詞[句]を伴って》『横たわる』,横になる / 《状態を表す副詞[句]を伴った》『置かれている』,ある / 《場所を表す副詞[句]を伴って》(ある場所に)『位置する』,ある / 《通例場所を表す副詞[句]を伴って》〈誤り・理由・責任・抽象的なものが〉見い出される,ある / 《場所を表す副詞[句]を伴って》地下に眠る,葬られている / 位置,方向;状態
『うそ』,希り / 〈人が〉『うそを言う』,偽る;(…に)うそを言う《+『to』+『名』》;(…について)うそを言う《+『about』+『名』(do『ing』)》 / 〈物事が〉欺く・「lie oneself out of 何々」で「嘘を言って(困難などから)逃れる」
横の,横断の;(線など)交わる / (幾何で)横軸の / 横断するもの(特に道路など) / (幾何で)横軸
リード(ドイツの叙情的歌曲)

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2014/12/09 07:55:29」(JST)

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[Wiki en表示]

A shoulder presentation refers to a malpresentation at childbirth where the baby is in a transverse lie (its vertebral column is perpendicular to that of the mother), thus the leading part (the part that enters first the birth canal) is an arm, shoulder, or the trunk. While a baby can be delivered vaginally when either the head or the feet/buttocks are the leading part, it usually cannot be expected to be delivered successfully with a shoulder presentation unless a cesarean section (C/S) is performed.

Frequency and causes

Shoulder presentations are uncommon (about 0.5% of births)^[1] as usually towards the end of gestation either the head or the buttocks start to enter the upper part of the pelvis anchoring the fetus in a longitudinal lie. It is not known in all cases of shoulder presentation why the longitudinal lie is not reached, but possible causes include bony abnormalities of the pelvis, uterine abnormalities such as malformations or tumors (fibroids), and other tumors in the pelvis or abdomen can also lead to a shoulder presentation. Other factors are a lax abdominal musculature, uterine overdistension (i.e. polyhydramnios), multiple gestation, placenta previa, a small fetus, or a fetus with some abnormality. Further, if the amniotic fluid sac ruptures the shoulder or arm may become wedged as a shoulder presentation.

Diagnosis

Inspection of the abdomen may already give a clue as it is wide from side to side. Usually performing the Leopold's maneuvers will demonstrate the transverse lie of the fetus.^[2] Ultrasound examination delivers the diagnosis and may indicate possible causes such as multiple gestation or a tumor. On vaginal examination, the absence of a head or feet/breech is apparent.

Shoulder presentations are classified into four types, based on the location of the scapula:

Left scapula-anterior (LSA)
Right scapula-anterior (RSA)
Left scapula-posterior (LSP)
Right scapula-posterior (RSP)

Management

While a transverse lie prior to labor can be manually versed to a longitudinal lie, once the uterus starts contracting the uterus normally will not allow any version procedure. A shoulder presentation is an indication for a C/S. Generally, as it is diagnosed early, the baby is not damaged by the time of delivery. With the rupture of the membranes, there is an increased risk of a cord prolapse as the shoulder may not completely block the birth canal. Thus the C/S is ideally performed before the membranes break.

Delivery of the second twin

The delivery of the second twin in a transverse lie with a shoulder presentation represents a special situation that may be amenable to a vaginal delivery. As the first twin has just been delivered and the cervix is fully dilated the obstetrician may perform an internal version, that is inserting one hand into the uterus, find the baby’s feet, and then bring the baby into a breech position and deliver the baby as such.^[3]

Impaction

During labor the shoulder will be wedged into the pelvis and the head lie in one iliac fossa, the breech in the other. With further uterine contractions the baby suffocates.^[1] The uterus continues to try to expel the impacted fetus and as its retraction ring rises, the musculature in the lower segments thins out leading eventually to a uterine rupture and the death of the mother.^[1]^[4] Impacted shoulder presentations contribute to maternal mortality.^[5] Obviously a cesarean section should be performed before the baby has died, but even when the baby has died or impaction has occurred, C/S is the method of choice of delivery, as alternative methods of delivery are potentially too traumatic for the mother. If the baby is preterm or macerated and very small a spontaneous delivery has been observed.^[1]

History

Internal version according to Siegemundin, 1690

Prior to the arrival of C/S the fetus usually died during protracted labor and the mother's life was at risk as well due to infection, uterine rupture and bleeding. On occasion, if the baby was macerated and small, it collapsed sufficiently to be delivered. The shoulder presentation was a feared obstetrical complication.

In 1690 Justine Siegemundin, a German midwife, published Die Kgl. Preußische und Chur-Brandenburgische Hof-Wehemutter. This treatise for midwives demonstrated abnormal presentations at birth and their management. She was the first to describe a two-handed method of performing an internal rotation of the baby to extract it as a breech (a variation of which is performed today on the second twin, see above) using a sling.^[6] The procedure was useful provided the fetus was not impacted. Once the uterus had contracted around the baby tightly, destructive interventions were used to save the life of the mother.^[7]

Note

Shoulder presentation is a malpresentation that is not to be confused with shoulder dystocia, a complication during the birth of a baby in a vertex presentation.

References

^ ^a ^b ^c ^d Hellman LM, Pritchard JA (1971). Williams Obstetrics, 14th Edition. Appleton Century Crofts. p. 872ff.
^ Lydon-Rochelle M, Albers L, Gotwocia J, Craig E, Qualls C (02-04-2007). "Accuracy of Leopold Maneuvrers in Screening for Malpresentation: A Prospective Study". Birth 20 (3): 132–5. PMID 8240620. Check date values in: |date= (help)
^ Rabinovici J Barkai G, Reichman B, Serr DM, Mashiach S (01-03-1988). "Internal podalic version with unruptured membranes for the second twin in transverse lie.". Obstet, Gynecol. 71 (3 Pt 1): 428–30. PMID 3347429. Check date values in: |date= (help)
^ Diab AE (2005). "Uterine ruptures in Yemen". Saudi Medical journal 26 (2): 264–9. PMID 15770303.
^ Chamiso B (October 1995). "Rupture of pregnant uterus in Shashemene Hospital, south Shoa, Ethiopia (a three year study of 57 cases).". Ethiop. Med. J. 33 (4): 251–7. PMID 8674491.
^ Speert H. Iconographia Gyniatrica. F. A. Davis (1973) ISBN 0-8036-8070-8. p. 257.
^ Mann RM (1856-04-14). "Case of Arm and Shoulder Presentation in Which Evisceration was Performed.". Association Medical Journal. PMC 2439677. Retrieved 2008-12-19.

External links

Institute and Museum of History of Science, see models 36-42

UpToDate Contents

全文を閲覧するには購読必要です。 To read the full text you will need to subscribe.

1. 横位の胎児の管理 management of the fetus in transverse lie
2. 外回転術 external cephalic version
3. 帝王切開：手技 cesarean delivery technique
4. 後頭横位 occiput transverse position
5. 臍帯脱出 umbilical cord prolapse

English Journal

PMID 26770066

Maurer-Cartan Forms for Fields on Surfaces: Application to Heart Fiber Geometry.

Piuze E, Sporring J, Siddiqi K.
IEEE transactions on pattern analysis and machine intelligence.IEEE Trans Pattern Anal Mach Intell.2015 Dec;37(12):2492-504. doi: 10.1109/TPAMI.2015.2408352.
We study the space of first order models of smooth frame fields using the method of moving frames. By exploiting the Maurer-Cartan matrix of connection forms we develop geometrical embeddings for frame fields which lie on spherical, ellipsoidal and generalized helicoid surfaces. We design methods fo
PMID 26539853

The Likelihood of Change in Fetal Presentation During the Third Trimester in Twin Pregnancies.

Melamed N1, Wong J, Asztalos E, Rosen H, Okby R, Barrett J.
Obstetrics and gynecology.Obstet Gynecol.2015 Dec;126(6):1231-6. doi: 10.1097/AOG.0000000000001128.
OBJECTIVE: To estimate the likelihood and identify predictors of spontaneous fetal version during the third trimester in twins using data from a multicenter randomized controlled trial on mode of delivery in twin pregnancies.METHODS: Women with twin pregnancies after 32 weeks of gestation in which t
PMID 26551181

Related Pictures

★リンクテーブル★

リンク元	「横位」「transversal」「transverse presentation」
関連記事	「lie」「transverse」

「横位」

Shoulder Presentation
	Classification and external resources
	A shoulder presentation with a prolapsed arm, by William Smellie
ICD-10	O64.4
ICD-9	660.01
MedlinePlus	002060