A bed frame 36 disclosed herein includes a calf section 72 with a foot end 74 and an upper end 76 longitudinally spaced from the foot end, an upper body section 54 with a head end 56 and a lower end 58 longitudinally spaced from the head end, and a medial section 66 longitudinally intermediate the calf and upper body sections. The bed frame is capable of assuming a chair state and a chair egress state. The upper body section and medial section define a sacral corner 68, and the calf section and medial section define a popliteal corner 70 spaced from the sacral corner by an intercorner distance. The intercorner distance is smaller in the chair egress state than in the chair state. A mattress 100 disclosed herein includes an upper body segment 102, a calf segment 116, and a medial segment 124 The lower end 106 of the upper body segment cooperates with the upper end 120 of the calf segment to define an intersegment distance. The mattress has a chair state in which the intersegment distance is a distance D1 and an egress state in which the intersegment distance is a distance D2 which is less than D1. A bed disclosed herein includes a frame whose intercorner distance is smaller in the chair egress state than in the chair state, and a mattress having a medial segment which is conformable to accommodate smaller and larger intercorner distances.