She walked on walls, turned everyday gestures into performance and helped create a new genre of postmodern dance. Now iconic American choreographer Trisha Brown has announced she is to retire, at the age of 76. Once at the forefront of the avant-garde Judson Church arts scene in Greenwich Village, she’s been innovating ever since, but poor health is forcing Brown to slow down. Although her company plans to continue, this week will be Brown’s last London appearance at its helm, in four intimate shows as part of this year’s Dance Umbrella festival. Here’s why you should think about going to her send-off.