ACETABULAR CUP POSITIONING TOOL AND METHOD OF POSITIONING AN ACETABULAR CUP

摘要

A positioning tool (1) has an elongated cylindrical section (15) for reversibly engaging an acetabular cup (2), which is insertable through a posterior opening (28) in the cup. The outer diameter of a proximal portion of the cylindrical section (15) is expandable to engage the inner wall (30b) of the cup in an interference fit to prevent movement of the cup relative to the tool and hold the cup in engagement with the tool to move the cup with movement of tool to place the cup for implanting at a desired position. The expanded portion of the tool may be contracted to release it from the cup after implantation. The proximal portion of the tool comprising the cylindrical first section (15) and tapered section (19), which is attached to the distal portion and separated therefrom by a partial transverse slot (22). Third section (15) is divided into semicircular sections (34, 35) by a diametrical vertical slot (20) therebetween. Diametrically opposite quadrants (29a, 29b) of the semicircular sections (34, 35) further contain elongated slots (26, 27) therethrough which are perpendicular to the vertical slot (20) and spaced from the edge (57) of the cylinder by a thin section (25). The outer diameter of the proximal portion of the cylindrical third section (15) may be expanded or contracted by pivoting the semicircular sections (34, 35) around the thin spaces (25) between the elongated slots and edges of the proximal portions. The tool further comprises means for causing the semicircular sections to move relative to each other to expand or contract the diameter of the cylindrical section (15).