Deep transverse perineal muscle

The Transversus perinei profundus (or deep transverse perineal) arises from the inferior rami of the ischium and runs to the median line, where it interlaces in a tendinous raphé with its fellow of the opposite side.

It lies in the same plane as the Sphincter urethræ membranaceæ; formerly the two muscles were described together as the Constrictor urethrae.