An intravertebral widening device (4) extends from a proximal end (8) to a distal end (10) along an extension axis (X), said distal end (10) having an elastically deformable element (56) suitable to pass from a relaxed configuration for placing the distal end (10) within a vertebral body (6) to a deformed configuration for forming a cavity within said vertebral body (6). The elastically deformable element (56) comprises at least one tab (60) having, along the longitudinal extension thereof, a varying thickness relative to a radial direction incident with said extension axis (X) and contained in a perpendicular plane to said extension axis (X), such as to vary the stiffness of at least one tab (60) along the extension thereof.