Dextral torsion

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A term denoting the situation in which the boundary between the fourth and fifth postcingular homologues (IV/V) approaches a middorsal position and thus usually lies proximal relative to the boundary between the third and fourth precingular homologues (4/5). It is as if the hyposome has been rotated proximally with regard to the episome. Such configurations are termed dextrally contorted. The present use of the term dextral is analogous to its use in structural geology in describing relative movements along faults. See also sinistral torsion and neutral torsion. Refer to Text-Figure 83C.