A bed assembly (10) includes a frame (22) which supports four curved mattresssupport panels (50-56) which are able to move with pivoting of the various partsof the frame (22). The curved panels (50-56) better conform to a patient'sbody shape and provide an effective lengthening of the mattress support (50-56),particularly when the back rest (30, 50) is raised to a sitting position. The supportpanels (50-56) are located below the pivot points of the frame (22), which furtherenhances the lengthening effect. The assembly also includes first and secondpatient retention panels (80, 82) with complementary edges (92, 94) which canslide over one another. A key pad unit (100) protrudes from the retention panel(80) at a convenient patient position and can be gripped by a p atient's hand.
