Curve of Carus

In obstetrics, the Carus curve, also called the pelvic axis, is an imaginary arc or semicircle within the pelvis, the radius of which is half the length of the true conjugate diameter and whose center is at the middle of the posterior surface of the pubic symphysis. It is used to describe the final course of the fetus during the delivery mechanism. The Carus curve is obtained by intersecting with each other the axes following the diameters of the planes existing in the upper and lower straits of the pelvis. The fetus goes by the Carus curve naturally, being especially useful during dystocia during labor or the use of artificial extraction techniques.

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