A clamping device configured to secure a strap to a rail of a support table or operating table is provided, which prevents the patient from slipping, provides optimal patient stability when the table is placed in angle positions, and eliminates patient re-positioning during surgical procedure. The clamping device includes a body portion having a plurality of rail arms that form a rail channel, the clamping device including a pivot jaw assembly with jaw rail flange portions coupled to sides of the body portion. The pivot jaw is hingedly operated between an open and closed position. The rail arms further include a strap channel configured to hold a strap disposed around the side rail, and to secure the strap to the rail using a clamp bar via force exerted on rail and jaw flange portions of the clamp assembly, to effectively clamp the strap to the table.