Technically, back labor occurs when the fetus is in a posterior position, with its face up and the back of its head pressing against your sacrum, or the back of your pelvis.

从技术上来说，背阵痛发生在胎儿处于背对的位置，它的脸朝上而后脑勺紧靠你的骶骨或者骨盆后方。

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Of these 98 anterior sacral injuries, 47 (48.0%) were complete, passing through the sacrum and exiting the posterior cortex.

在上述98例骶骨前部损伤中，47(48.0%)处为完全损伤，其骨折线贯穿骶骨、穿出后方皮质。

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Complicated pelvic fracture including sacrum bone fracture mostly displays pelvic posterior ring injuries.

复杂的骨盆骨折多数存在骨盆后环损伤，包括骶骨骨折。

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