Osteosynthesis screw with reduced radial compression
View Patent ↗The invention concerns an osteosynthesis screw ( 1 ) formed from a core ( 2 ) externally provided with a helical thread ( 3 ), said screw comprising a distal penetration portion and a proximal portion forming the head of the screw ( 6 ) and having a conical longitudinal section characterized in that the proximal portion comprises annular notches which are formed in the thickness of the core ( 2 ) and in the gaps between the threads of said proximal portion in such a way as to reduce the radial pressure during screwing.—Surgical device.
1. An osteosynthesis screw ( 1 ) formed by a core ( 2 ) provided externally with a helical thread ( 3 ), said screw having a distal penetration portion ( 4 ) and a proximal portion ( 5 ) forming the screw head ( 6 ) and having a conical longitudinal section,
wherein the proximal portion ( 5 ) forming the screw head ( 6 ) and having the conical longitudinal section includes circular notches ( 12 ) that are formed in the thickness of the core ( 2 ) and in the inter-thread gaps ( 13 ) of said proximal portion ( 5 ), said circular notches, as disposed and configured, reducing radial pressure during screw tightening, and
wherein the circular notches ( 12 ) that are formed in the thickness of the core ( 2 ) and in the inter-thread gaps ( 13 ) of said proximal portion ( 5 ) extend generally in a circular direction relative to a circular section of the core ( 2 ).
2. The osteosynthesis screw ( 1 ) according to claim 1 , wherein a plurality of the circular notches ( 12 ) are axially aligned one after another in the inter-thread gaps ( 13 ) to form at least one row of notches ( 12 ).
3. The osteosynthesis screw ( 1 ) according to claim 2 , wherein the circular notches ( 12 ) are provided in adjacent inter-thread gaps ( 13 ).
4. The osteosynthesis screw ( 1 ) according to claim 2 , wherein a plurality of rows of circular notches ( 12 ) are angularly distributed at regular intervals around the periphery of the core ( 2 ).
5. An osteosynthesis screw ( 1 ), formed by a core ( 2 ) provided externally with a helical thread ( 3 ), said screw having a distal penetration portion ( 4 ) and a proximal portion ( 5 ) forming the screw head ( 6 ) and having a conical longitudinal section,
wherein the proximal portion ( 5 ) forming the screw head ( 6 ) and having the conical longitudinal section includes circular notches ( 12 ) that are formed in the thickness of the core ( 2 ) and in the inter-thread gaps ( 13 ) of said proximal portion ( 5 ), said circular notches, as disposed and configured, reducing radial pressure during screw tightening, and
wherein the circular notches ( 12 ) form depressions ( 15 ) of concave curvature, defining a leading edge ( 16 ) that is downstream relative to a screw-tightening direction V.
6. An osteosynthesis screw ( 1 ) formed by a core ( 2 ) provided externally with a helical thread ( 3 ), said screw having a distal penetration portion ( 4 ) and a proximal portion ( 5 ) forming the screw head ( 6 ) and having a conical longitudinal section,
wherein the proximal portion ( 5 ) forming the screw head ( 6 ) and having the conical longitudinal section includes circular notches ( 12 ) that are formed in the thickness of the core ( 2 ) and in the inter-thread gaps ( 13 ) of said proximal portion ( 5 ), said circular notches, as disposed and configured, reducing radial pressure during screw tightening, and
wherein the circular notches ( 12 ) form depressions ( 15 ) of concave curvature, defining a leading edge ( 16 ) that is downstream relative to a screw-tightening direction V, each of the depressions ( 15 ) being provided with a closed upstream edge ( 19 ) forming a partition that is orthogonal to the periphery of the core ( 2 ).
7. The osteosynthesis screw ( 1 ) according to claim 1 , wherein the circular notches ( 12 ) are associated with self-tapping cutouts ( 20 ) formed in the thickness of the helical thread ( 3 ).
8. The osteosynthesis screw ( 1 ) according to claim 1 , further comprising a cannula.
9. The osteosynthesis screw ( 1 ) according to claim 1 , wherein the helical thread ( 3 ) extends over the entire length of the screw.
10. The osteosynthesis screw ( 1 ) according to claim 1 , wherein the distal penetration portion ( 4 ) is self-tapping.
11. The osteosynthesis screw ( 1 ) according to claim 1 , wherein said screw is a non-compressive screw.
12. The osteosynthesis screw ( 1 ) according to claim 3 ,
wherein a plurality of rows of the circular notches ( 12 ) are angularly distributed at regular intervals around the periphery of the core ( 2 ).
13. The osteosynthesis screw ( 1 ) according to claim 2 , wherein the circular notches ( 12 ) form depressions ( 15 ) of concave curvature, defining a leading edge ( 16 ) that is downstream relative to a screw-tightening direction V.
14. The osteosynthesis screw ( 1 ) according to claim 3 , wherein the circular notches ( 12 ) form depressions ( 15 ) of concave curvature, defining a leading edge ( 16 ) that is downstream relative to a screw-tightening direction V.
15. The osteosynthesis screw ( 1 ) according to claim 4 , wherein the circular notches ( 12 ) form depressions ( 15 ) of concave curvature, defining a leading edge ( 16 ) that is downstream relative to a screw-tightening direction V.
16. The osteosynthesis screw ( 1 ) according to claim 13 , wherein the depression ( 15 ) is provided with a closed upstream edge ( 19 ) forming a partition.
17. The osteosynthesis screw ( 1 ) according to claim 6 , wherein the circular notches ( 12 ) are associated with self-tapping cutouts ( 20 ) formed in the thickness of the helical thread ( 3 ).
18. The osteosynthesis screw ( 1 ) according to claim 17 , further comprising a cannula.
19. The osteosynthesis screw according to claim 1 , wherein a diameter in the conical longitudinal section including the circular notches formed therein decreases in a direction from the screw head in the proximal portion towards the distal penetration portion.