A surgical device (1), which may advantageously perform the functions of both a retractor and a distractor, comprising: two retractor blades (2) facing each other and held in a common frame (4), the retractor blades (2) being insertable into a surgical incision in a patient and moveable away from each other along a main axis (x) so as to widen the surgical incision; and a connecting pin (3) attached at a distal end (20) of each retractor blade (2), each connecting pin (3) being attachable to a pedicle screw (100) anchored to respective vertebrae of the patient, so that moving away the two retractor blades (2) along the main axis (x) determines a distraction of the vertebrae.