Surgical nail
The surgical nail, here in the form of an intramedullary nail, has a central axis, a longitudinal borehole with a diameter D extending coaxially with the central axis, a casing with an inner surface and a transverse borehole, extending transversely to the central axis with the cross-sectional profile F and the borehole axis. A component, which narrows the cross-sectional profile F, is provided in the longitudinal borehole in the region of the transverse borehole. By these means, the clearance, which is usually present between the medullary nail and the locking screws that have been introduced therein, can be eliminated without risk and an improved holding force as well as an improved guiding effect between the locking screw and the medullary nail can be achieved.
1. An intramedullary nail comprising:
a nail body having a central longitudinal axis, an outer wall surrounding a longitudinal bore and defining an inner wall surface, and a transverse opening through the outer wall, the transverse opening having a central axis and a cross-sectional profile F and configured for receiving a bone fixation element;
a longitudinal component disposed within the longitudinal bore and extending partially into the transverse opening to abut against a bone fixation element inserted through the transverse opening without being penetrated by the bone fixation element; and wherein the inner wall surface of the nail includes a longitudinal groove having a partially circular cross section that extends parallel to the central axis, the groove is configured and dimensioned for receiving the component.
2. The device of claim 1 , wherein the component is integrally attached to the inner wall surface of the nail body.
3. The device of claim 1 , wherein the component is selected from the group consisting of a pin, a stud, a cable, section of wire.
4. The device of claim 1 , wherein the component is aligned parallel to the central longitudinal axis of the nail.
5. The device of claim 4 , wherein the portion of the component that contacts the bone fixation element when inserted through the transverse opening is aligned parallel to the central longitudinal axis.
6. The device of claim 1 , wherein the nail and the component are formed of the same material.
7. The device of claim 1 , wherein the component is formed of polyethylene, a high-molecular weight polyethylene (HMWPE) or other biocompatible plastic.
8. The device of claim 1 , wherein the component is formed of a bioabsorbable polymer or copolymer.
9. The device of claim 1 , wherein the cross-sectional profile F of the transverse opening has a maximum length a in the direction of the longitudinal central axis of the nail and a maximum width b perpendicularly thereto, where a>b.
10. The device of claim 9 , wherein the bone fixation element nail is a bone screw with an external thread having a maximum diameter d, where a>d<b.
11. The device of claim 10 , wherein the diameter d is at least 5% smaller than the smaller of the two dimensions a, b.
12. The device of claim 1 , wherein the component is a separate element configured for introduction into the longitudinal bore of the nail at the time of a surgical procedure.
13. The device of claim 1 , wherein the partially circular groove defines a central angle greater than 180 degree.
14. The device of claim 1 , wherein the longitudinal bore of the nail has a diameter D, and the component has a maximum thickness of P>0.01 D protruding radially into the longitudinal bore.
15. The device of claim 14 , wherein the component has a maximum thickness of P>0.05 D protruding radially into the longitudinal borehole.
16. An intramedullary nail comprising:
a nail body having a central longitudinal axis, an outer wall surrounding a longitudinal bore and defining an inner wall surface, wherein the inner wall surface of the nail includes a longitudinal groove having a partially circular cross section that extends parallel to the central axis, the groove is configured and dimensioned for receiving a component, and a transverse opening through the outer wall, the transverse opening having a central axis and a cross-sectional profile F and configured for receiving a bone fixation element; and
a longitudinal component aligned parallel to the longitudinal central axis of the nail and configured and dimensioned for insertion into the longitudinal groove such that the longitudinal component extends partially into the transverse opening to abut against a bone fixation element inserted through the transverse opening without being penetrated by the bone fixation element.
17. A method for repairing bone fractures comprising:
providing an intramedullary nail for insertion into the medullary canal of a fractured bone, the intramedullary nail having a nail body with a central longitudinal axis, an outer wall surrounding a longitudinal bore, an inner wall surface, and a transverse opening through the outer wall, where the transverse opening has a cross-sectional profile F and is configured for receiving a bone fixation element and wherein the inner wall surface of the nail includes a longitudinal groove having a partially circular cross section that extends parallel to the central axis, the groove is configured and dimensioned for receiving a component;
inserting a longitudinal component within the longitudinal bore of the nail such that the longitudinal component extends partially into the transverse opening;
inserting at least one bone fixation element through the transverse opening in the intramedullary nail such that the bone fixation element abuts the longitudinal component without penetrating the longitudinal component.