Method of performing a minimally-invasive intervention

Apparatus for use in an operating theater equipped with a surgical table, comprises a lifting frame attachable to the surgical table and adapted for lifting a body part of a subject undergoing a surgical procedure upon the surgical table, and comprising an upright support post incorporating a jack, and a lifting arm pivotally mounted upon the post, whereby the arm can be turned about the upright support post on thrust bearing to either overhang the surgical table, or be pivoted away to permit access to the surgical table. The arm is adapted to support a retractor that comprises a blade portion incorporating a plurality of independent lighting devices positioned in light ports and configured to provide discrete illumination selectively to zones within the surgical field according to (a) a predetermined sequence program, or (b) a sequence determined by a user of the retractor.