Method and apparatus for osteosynthesis

1. A proximal humeral plate assembly comprising:

a first plate defining a window, the first plate having a first major surface adapted to conform to a native bone structure;

a coupler formed on a second major surface of the first plate opposite the first major surface;

a second plate adapted to engage a mating surface on the coupler and to cover the window, the second plate including through holes adapted to receive bone screws, the second plate further adapted to conform to the native bone structure; and

a guide adapted to engage the mating surface on the coupler and to guide at least one of a cutting tool and a dilation tool, the engagement between the guide and the mating surface on the coupler securing the guide to the first plate.

2. The bone plate system of claim 1 , wherein mating surface on the coupler is adapted to slidingly receive the guide.

3. The bone plate system of claim 1 , wherein the guide is adapted to align the at least one of the cutting tool and the dilation tool at a predetermined angle with respect to the first plate upon engagement with the mating surface.

4. The bone plate system of claim 1 , wherein the guide includes a hollow shaft sized to receive the at least one of the cutting tool and the dilation tool.

5. The bone plate system of claim 1 , wherein the window is non-circular and has a length extending generally parallel to a longitudinal axis of the first plate.

6. The bone plate system of claim 5 , wherein the first plate includes an I-shaped cross-section proximate to longitudinal sides of the window.

7. The bone plate system of claim 1 , wherein the coupler includes an L-shaped cross section.

8. The bone plate system of claim 1 , wherein the coupler and the first plate define a longitudinal channel adjacent to the window.

9. The bone plate system of claim 8 , wherein the guide includes a base adapted to slidably engage the longitudinal channel.

10. The bone plate system of claim 1 , wherein the second plate includes a pin hole oriented to receive a pin at an angle.

11. The bone plate system of claim 1 , wherein the first plate includes a first partial hole and the second plate includes a second partial hole, the first partial hole and the second partial hole being adapted to receive a set screw to fix the second plate to the first plate.

12. The bone plate system of claim 1 , wherein the first plate includes a first beveled edge and the second plate includes a second beveled edge, the first beveled edge and the second beveled edge being adapted to engage each other to secure the second plate relative to the first plate.

13. The bone plate system of claim 1 , wherein the engagement between the guide and the mating surface on the coupler movably secures the guide to the first plate.

14. The bone plate system of claim 1 , wherein the second plate is sized to fit within the window.

15. The bone plate system of claim 1 , wherein an outer perimeter of the second plate conforms to an inner perimeter of the window.

16. A proximal humeral plate assembly comprising:

a first plate having a bone-engaging first surface and an opposed second surface, the first plate defining a window extending through the first and second surfaces, the bone-engaging first surface adapted to conform to a proximal humerus;

a slide mechanism formed on the opposed second surface of the first plate;

a second plate slidably engaged with a mating surface on the slide mechanism and supported by the first plate within the window, the second plate including through holes adapted to receive bone screws, the second plate further adapted to conform to the proximal humerus; and

a guide adapted to engage the mating surface on the slide mechanism and to guide at least one of a cutting tool and a dilation tool, the engagement between the guide and the mating surface on the slide mechanism securing the guide to the first plate.

17. The proximal humeral plate assembly of claim 16 , wherein the guide is adapted to slidably engage the mating surface on the slide mechanism.

18. The proximal humeral plate assembly of claim 16 , wherein the mating surface on the slide mechanism and the second surface of the first plate define a longitudinal channel adjacent to the window.

19. The proximal humeral plate assembly of claim 18 , further comprising a rail formed on the second plate and adapted to engage the longitudinal channel.

20. The proximal humeral plate assembly of claim 16 , wherein the engagement between the guide and the mating surface on the slide mechanism movably secures the guide to the first plate.

21. The proximal humeral plate assembly of claim 16 , wherein the second plate is sized to fit within the window.

22. The proximal humeral plate assembly of claim 16 , wherein an outer perimeter of the second plate conforms to an inner perimeter of the window.

23. A proximal humeral plate assembly comprising:

a first plate having a bone-engaging first surface and an opposed second surface, the first plate defining a window extending through the first and second surfaces, the bone-engaging first surface adapted to conform to a proximal humerus;

a slide mechanism formed on the opposed second surface of the first plate;

a second plate configured to slidably engage a mating surface on the slide mechanism, the second plate being sized to fit within the window and having an outer perimeter that conforms to an inner perimeter of the window such that the second plate covers the window when the second plate is placed within the window, the second plate including through holes adapted to receive bone screws, the second plate having a bone-engaging surface adapted to conform to the proximal humerus; and

a guide adapted to engage the mating surface on the slide mechanism and to guide at least one of a cutting tool and a dilation tool, the engagement between the guide and the mating surface on the slide mechanism securing the guide to the first plate to prevent movement of the guide in a direction perpendicular to the first and second surfaces of the first plate.