Abstract: A hospital mattress which is flexible and permits head elevation and knee flexion has removably securable inserts which can be repeatedly removed or replaced and secured without requiring substantial displacement of the patient. A body of resilient material, preferably closed-cell polymer foam, is utilized to form the mattress. The portion of the foam body disposed to underlie a predetermined portion of the patient's body, typically the patient's trunk, is removed. A flexible, generally impervious material, such as vinyl, is utilized to cover all exterior surfaces of the foam body and inserts, and to form a floor in the cut-out section of the foam body. The inserts are cushions adapted to be received in the recess defined by the cut-out portion. Each insert cushion is made of a block of resilient material and is covered with an impervious material.