초록 ▼

A bone cement plug for fitting into the intramedullary canal within a bone to restrict flow of bone cement during surgery comprises a sleeve (2) whose wall is circumferentially continuous and has an outer surface (10) for contacting the wall (32) of the canal. The sleeve (2) is formed from a deforma

A bone cement plug for fitting into the intramedullary canal within a bone to restrict flow of bone cement during surgery comprises a sleeve (2) whose wall is circumferentially continuous and has an outer surface (10) for contacting the wall (32) of the canal. The sleeve (2) is formed from a deformable material so that it can be expanded transversely to contact the surface (32) of the canal. The plug includes an expander which can be drawn through the cavity (12) in a direction generally along the axis of the sleeve (2), to cause the sleeve (2) to expand transversely to contact the surface (32) of the canal. The inner surfaces of the wall converge towards the end (16) of the sleeve (2) towards which the expander is drawn to cause the sleeve (2) to expand to contact the surface (32) of the canal.

대표청구항 ▼

The invention claimed is: 1. A bone cement plug for fitting into the intramedullary canal within a bone to restrict flow of bone cement during surgery, comprising: a sleeve having a longitudinal axis, an outer surface configured to contact the wall of the canal, and inner surfaces configured to def

The invention claimed is: 1. A bone cement plug for fitting into the intramedullary canal within a bone to restrict flow of bone cement during surgery, comprising: a sleeve having a longitudinal axis, an outer surface configured to contact the wall of the canal, and inner surfaces configured to define an internal cavity whose diameter decreases from a distal end to a proximal end, whereat the internal cavity communicates with an opening formed in the outer surface, the sleeve being formed from a deformable material and configured to be expanded transversely to contact the surface of the canal; an expander comprising a shaft having a distal end and a transverse portion that extends radially from the distal end of the shaft, the shaft dimensioned to extend through the opening; and a washer disposed on the shaft, and having a plurality of radially slots formed therein extending from the outside edge of the washer toward the inside edge thereof; and wherein the expander is movable within the cavity in a direction generally along the longitudinal axis from a distal position to a proximal position, whereat the washer contacts the internal cavity to cause the wall of the sleeve to expand transversely to contact the surface of the canal, wherein the transverse portion of the expander has a diameter, the washer has a first configuration, where the diameter of the washer is approximately equal to the diameter of the transverse portion, and a second configuration, where the diameter of the washer is greater than the transverse portion, and wherein when the expander is at the distal position, the washer is in the first configuration, and when the expander is in the proximal position, the washer is in the second configuration such that the outer perimeter of the washer contacts the internal cavity to cause the wall of the sleeve to expand transversely to contact the surface of the canal. 2. The bone cement plug of claim 1, wherein the sleeve has an end wall at the proximal end thereof and is formed as a single body with the wall of the sleeve. 3. The bone cement plug of claim 1, wherein the shaft is configured to be frangible at a defined line of weakness. 4. The bone cement plug of claim 1, wherein the shaft and transverse portion of the expander are formed as a single component. 5. The bone cement plug of claim 4, wherein the shaft and the transverse portion of the expander are formed from a resorbable material. 6. The bone cement plug of claim 1, wherein the angle between the inner surface of the wall and the longitudinal axis at the distal end of the sleeve is at least about 20 degrees. 7. The bone cement plug of claim 1, wherein the angle between the inner surface of the wall and the longitudinal axis at the distal end of the sleeve is not more than about 50 degrees. 8. The bone cement plug of claim 1, wherein the outer surface of the sleeve has surface features to promote engagement with the bone surface of the intramedullary canal. 9. The bone cement plug of claim 1, wherein the sleeve has at least one indent in the surface which defines the internal cavity, the indent extending around the internal cavity approximately in a plane that is perpendicular to the axis of the sleeve. 10. The bone cement plug of claim 1, wherein the hardness of the material of the sleeve is at least about 30 Shore A. 11. The bone cement plug of claim 1, wherein the hardness of the material of the sleeve is not more than about 75 Shore A. 12. The bone cement plug of claim 1, wherein the sleeve is formed from a resorbable material. 13. An assembly for use in orthopaedic surgery, comprising: a bone cement plug of claim 1 and an instrument for locating the plug in the intramedullary canal within a bone. 14. The assembly of claim 13, wherein the expander comprises a shaft that extends generally along the longitudinal axis, and wherein the instrument includes a socket for engaging the shaft on the expander. 15. The assembly of claim 13, which includes a drive unit by which the expander can be drawn into the sleeve to cause the expander to move from the distal position to the proximal position. 16. The bone cement plug of claim 1, wherein the transverse portion of the expander has a diameter, the washer has a conical configuration, where the diameter of the washer is approximately equal to the diameter of the transverse portion, and a flattened configuration, where the diameter of the washer is greater than the transverse portion, and wherein when the expander is at the distal position, the washer is in the conical configuration, and when the expander is in the proximal position, the washer is in the flattened configuration such that the outer perimeter of the washer contacts the internal cavity to cause the wall of the sleeve to expand transversely to contact the surface of the canal. 17. A bone cement plug for fitting into the intramedullary canal within a bone to restrict flow of bone cement during surgery, comprising: a sleeve having an outer surface configured to contact the wall of the canal, an internal cavity and being formed from a deformable material; an expander comprising a shaft having a distal end and a transverse portion that extends radially from the distal end of the shaft, the transverse portion having a diameter; and a washer disposed on the shaft, and having a plurality of radially slots formed therein extending from the outside edge of the washer toward the inside edge thereof, the washer having a conical configuration, where the diameter of the washer is approximately equal to the diameter of the transverse portion, and a flattened configuration, where the diameter of the washer is greater than the transverse portion, wherein the expander is movable within the cavity from a distal position, whereat the washer is in the conical configuration, to a proximal position, whereat the washer is in the flattened configuration and the outer perimeter of the washer contacts the internal cavity to cause the wall of the sleeve to expand transversely to contact the surface of the canal.