Extended Lumbar Lordosis/Kyphosis: These backrests are simply one-piece backrests made from two halves but joined by a locking hinge. This hinge allows the vertical profile of the backrest to be adjusted to suit more severe degrees of Lumbar Lordosis or Kyphosis. In order to maximise the convex curvature for a severe Lumbar Kyphosis, the backrest segments can be individually inverted and then reconnected with the locking hinge. Each segment contains two internal horizontal straps. Ideally, the upper strap of the lower segment should be positioned vertically so that it will support the pelvis at a level just below the Ischial crest. <<<back