Seat system for preventing decubiti

Claim 1

A seat system for providing support for a seated occupant with a minimum of pressure on the occupant's seat bones so as to retard the formation of decubitous sores in tissue adjacent to those bones comprised of: a rigid base having a pair of side edges and having a seating surface including a rearward section for receiving the occupant's buttock and a forward section for receiving the occupant's thighs; the forward section having a pair of troughs between the side edges running forwardly from the rearward section and separated by a central ridge for supporting the thighs in an abducted position; the rearward section having a pair of wings formed of sloped support surfaces running inwardly and downwardly toward one another from either side edge, said support surfaces terminating in an inner edge defining a void generally mushroomed in cross-sectional shape having a relatively wide laterally extending head portion located interiorly and centrally of the rearward section of the seating surface and a relatively narrow stem portion extending rearwardly and centrally from the head portion through said rearward section, the wings extending rearwardly of the forward section of the seating surface and each wing including an enlarged portion as its rearmost end in opposed relation to the other for providing support at the rearward end of the base to prevent rearward sliding of the occupant; the rearward section also having a central support member for preventing forward sliding of the occupant, the central support member tapering forwardly and sloping upwardly from the head portion of the void to the central ridge of the forward section; the wings, including their enlarged portions, and the central support member of the rearward section of the seating surface having the overall shape of a partial oval bowl surrounding the void with its longer axis running transversly of the base through the void and the troughs of the forward section of the seating surface flowing smoothly into the wings, whereby an occupant may be positioned on said base with his buttock in the rear section, his ischial bones over the head portion of the void, his coccyx over the stem portion of the void and his thighs in the troughs; a deformable cushion having an overall peripheral shape similar to that of the seating surface of the base, including a pair of wings defining a void of the same general size and shape as that of the base; and means for securing the cushion to the base with the voids of each in approximate registration.