In 1972 Karen Kelsall first performed this stretch in competition and as a result, the move was named after her. Over the past 50 years, it has gained a number of other names including a ‘Scorpion,’ ‘Reverse Needle’ among others.
When the back leg is straight, as in the photo, this pose is stunning. However, it can also be done with a slightly curved back leg and and arched back. The key things to look for are:
straight base leg
foot parallel to the body … not turned inwards (pigeon toed)
a good grip on the foot
This is an advanced pose and very difficult to hold in place for someone not ready to perform it. It requires excellent flexibility and strength as well as balance. It should not be performed by those not ready to do it as it can also injure the back.