These are popular crutches that provide a single or double adjustment. They can be adjusted in terms of floor-to-handgrip height and the distance between the cuff and the handgrip in case of double adjustable crutches. Single adjustable elbow crutches allow floor-to-handgrip height adjustment only. Elbow crutches are available in two styles of cuff: open or closed. An open cuff is semi-circular in shape and provides a support to brace the forearm against in the step-through phase of walking. A closed cuff is an incomplete ring that prevents the forearm from slipping forwards out of place and holds the crutch on the arm.