Patent attributes
Apparatus, systems, and methods are disclosed involving a seat cushion configured as a partially-open annular ring, including a circular hollow space in a center of the ring, and a radial-arc-shaped opening in the ring forming a trapezium-shaped hollow space. The cushion includes a top section, a middle section, and a base section, in which the top and middle sections form the partially-open annular ring. Both the circular hollow space and the trapezium-shaped hollow space are located corresponding to the user's spine and coccyx, with the trapezium-shaped hollow space located on a rear portion of the cushion. The circular hollow space frees the perineal region from external compression by avoiding having any portion of the center of the seat cushion pressing against it, and the trapezium-shaped hollow space frees the sacrococcygeal region from external compression by not having any portion of partially-open annular ring of the seat cushion pressing against it.