A ratchet assembly for multi-dimensional movement and placement of a retractor blade comprising: a retractor blade holder shaped and dimensioned to receive a stem of a retractor blade, the retractor blade holder comprising a locking mechanism that enables selective lateral adjustment of the retractor blade relative to the retractor blade holder; a housing member to which the retractor blade holder is mated, wherein the retractor blade holder is vertically pivotable with respect to the housing member to enable selective vertical pivoting adjustment of the retractor blade relative to the housing member; a rotating indexer mated to the housing member, wherein the housing member is rotatable with respect to the rotating indexer so that the retractor blade holder, the housing member and the retractor blade are able to selectively rotate about the longitudinal axis of the rotating indexer, and wherein the rotating indexer is shaped and dimensioned to mount onto a rim of a surgical support; characterized in that the ratchet assembly includes a self-retaining locking mechanism that simultaneously locks or unlocks the position of the housing member relative to the rotating indexer and the position of the rotating indexer and the entire ratchet assembly onto the rim of the surgical support; and wherein the self retaining locking mechanism comprises a spring loaded lever, a spring loaded key and a spring loaded retention clip and wherein the spring loaded key interfaces with and engages a circumferential slot formed on the rotating indexer to lock the position of the housing member relative to the rotating indexer, and to lock the position of the rotating indexer and the entire ratchet assembly onto the rim of the surgical support with the spring loaded retention clip, wherein the rotating indexer is adapted to be pushed back into the housing member to cause the spring loaded key to fall into the circumferential slot and thereby lock the position of the rotating indexer within the housing member and cause a hook shaped retention clip of the spring loaded retention clip to be forced into a closed position and thereby lock the entire ratchet assembly onto the rim of the surgical support. a retractor blade holder shaped and dimensioned to receive a stem of a retractor blade, the retractor blade holder comprising a locking mechanism that enables selective lateral adjustment of the retractor blade relative to the retractor blade holder; a housing member to which the retractor blade holder is mated, wherein the retractor blade holder is vertically pivotable with respect to the housing member to enable selective vertical pivoting adjustment of the retractor blade relative to the housing member; a rotating indexer mated to the housing member, wherein the housing member is rotatable with respect to the rotating indexer so that the retractor blade holder, the housing member and the retractor blade are able to selectively rotate about the longitudinal axis of the rotating indexer, and wherein the rotating indexer is shaped and dimensioned to mount onto a rim of a surgical support; characterized in that the ratchet assembly includes a self-retaining locking mechanism that simultaneously locks or unlocks the position of the housing member relative to the rotating indexer and the position of the rotating indexer and the entire ratchet assembly onto the rim of the surgical support; and wherein the self retaining locking mechanism comprises a spring loaded lever, a spring loaded key and a spring loaded retention clip and wherein the spring loaded key interfaces with and engages a circumferential slot formed on the rotating indexer to lock the position of the housing member relative to the rotating indexer, and to lock the position of the rotating indexer and the entire ratchet assembly onto the rim of the surgical support with the spring loaded retention clip, wherein the rotating indexer is adapted to be pushed back into the housing member to cause the spring loaded key to fall into the circumferential slot and thereby lock the position of the rotating indexer within the housing member and cause a hook shaped retention clip of the spring loaded retention clip to be forced into a closed position and thereby lock the entire ratchet assembly onto the rim of the surgical support.