A woman's legs can remain flat or raised toward her chest, or wrapped around the penetrating partner at various heights: at the back of the legs, at the buttocks or back or over the shoulders, in a position called the "Wiener Auster" or Viennese oyster. In the higher leg positions the woman's legs may need some support, which may be achieved by crossing the ankles behind the partner or resting on his shoulders. She may also hold them with her hands or cross her arms around them at the knees. Some are flexible enough to cross the legs behind their heads. Alternatively, her partner may hold her legs up. Separating straight legs carry the risk of muscle pull of thigh muscles. The laying by the partner on raised legs puts excessive pressure on the woman's back.