Disposable flex reamer
View Patent ↗A single use intramedullary reamer comprised of a reamer head assembly and a reamer shaft. The reamer head assembly further comprising a series of reamer blades that reside in a series of surface slots that are helically oriented around the cylindrical body. The series of reamer blades are bonded with the cylindrical body through induction bonding.
1. A reamer head assembly, comprising:
a) a body comprising an annular outer surface, a proximal body end extending to a distal body end along a longitudinal axis, at least two body slots, each body slot having a slot length and a slot depth, the slots positioned within the annular outer surface of the body such that the slot length is not parallel with the longitudinal axis as it extends from the proximal body end to the distal body end, each body slot having a first slot angle measured between the slot length and the longitudinal axis of the body;
b) at least two continuous reamer blades, each reamer blade comprising a blade length extending from a proximal blade end adjacent to the proximal body end to a distal blade end adjacent to the distal body end, wherein each reamer blade comprises a reamer blade attachment portion and a reamer blade cutting portion partitioned between the proximal and distal blade ends by a reamer blade transition line that extends along the reamer blade length; and
c) wherein the reamer blades are positioned about the body, spaced apart from each other by a blade separation distance with a blade separation area therebetween, such that each reamer blade attachment portion is positioned within its respective body slot, the reamer blade cutting portion extending outwardly from the outer surface of the body and wherein each reamer blade is bent at an angle along the transition line such that the blade cutting portion and the blade attachment portion are not coplanar.
2. The reamer head assembly of claim 1 wherein the angle between the reamer blade attachment portion and the blade cutting portion is about 85° to about 175°.
3. The reamer head assembly of claim 1 wherein the blade separation distance ranges from about 0.3 mm to about 15.0 mm.
4. The reamer head assembly of claim 1 wherein the blade separation area is defined by:
[
Cavity
Cross
Sectional
Area
-
Reamer
Cross
Sectional
Area
]
Number
of
Insert
Blades
wherein the cavity cross sectional area is equal to a cross sectional area of a cavity within a bone formed by the reamer head assembly, and the reamer cross sectional area is the combined cross sectional areas of the body and the reamer blades.
5. The reamer head assembly of claim 1 wherein the body slot has a second slot angle, the second slot angle measured between the slot depth and a radial axis extending perpendicularly from the longitudinal axis of the body.
6. The reamer head assembly of claim 5 wherein the first slot angle is from about 5° to about 30° and the second slot angle is from about 5° to about 45°.
7. The reamer head assembly of claim 1 wherein the cutting surface extends from a forward blade surface, located adjacent the body distal end to a rearward relief surface, located adjacent the body proximal end, a bone cutting surface disposed therebetween, the bone cutting surface having an angled surface measuring from about 40° to about 50° with respect to the longitudinal axis of the body.
8. The reamer head assembly of claim 1 wherein each reamer blade has a relief angle and a rake angle.
9. The reamer head assembly of claim 8 wherein the relief angle measures from about 1° to about 25° and the rake angle measures from about 5° to about 25°.
10. The reamer head assembly of claim 1 wherein the reamer blade is composed of a material selected from the group consisting of stainless steel, MP35N, titanium, and combinations thereof.
11. The reamer head assembly of claim 1 wherein the body is composed of a moldable biocompatible polymeric material.
12. The reamer head assembly of claim 1 wherein the proximal body end is connectable to a reamer shaft.
13. A reamer comprising:
a) a body comprising an annular outer surface, a proximal body end extending to a distal body end along a longitudinal axis, the proximal body end connectable to a reamer shaft, at least two body slots, each slot having a slot length and a slot depth, the body slots positioned within the annular outer surface of the body such that the slot length is not parallel with the longitudinal axis as it extends from the proximal body end to the distal body end, each body slot having a first slot angle measured between the body slot length and the longitudinal axis of the body;
b) at least two continuous reamer blades, each reamer blade having a reamer blade thickness and a reamer blade length extending from a proximal reamer blade end adjacent to the proximal body end to a distal reamer blade end adjacent to the distal body end, the reamer blades further comprising a reamer blade attachment portion and a reamer blade cutting portion partitioned between the proximal and distal reamer blade ends by a reamer blade transition line that extends parallel to the reamer blade length, each reamer blade is bent at an angle along the transition line such that the blade cutting portion and the blade attachment portion are not coplanar; and
c) wherein the reamer blades are positioned about the body, spaced apart from each other by a blade separation distance with a blade separation area therebetween, such that the reamer blade attachment portion is positioned within its respective body slot, the reamer blade cutting portion extending outwardly from the outer surface of the body, the reamer blades further comprising a forward blade cutting surface positioned adjacent the distal body end and a rearward relief blade surface positioned adjacent the proximal body end.
14. The reamer of claim 13 wherein the angle between the reamer blade attachment portion and the blade cutting portion is about 85° to about 175°.
15. The reamer of claim 13 wherein the blade separation distance ranges from about 0.3 mm to about 15.0 mm.
16. The reamer of claim 13 wherein the body slot further comprises a second slot angle, the second slot angle measured between the slot depth and a radial axis extending from the longitudinal axis of the body.
17. A reamer head assembly comprising:
a) a body comprising an annular outer surface, a proximal body end extending to a distal body end along a longitudinal axis, at least two body slots, each slot having a slot length and a slot depth positioned within the annular outer surface of the body such that the slot length is not parallel with the longitudinal axis as it extends from the proximal body end to the distal body end, the slot depth penetrating through a portion of the outer surface of the body, each body slot further comprising a first slot angle and a second slot angle, the first slot angle measured between the slot length and the longitudinal axis, the second slot angle measured between the slot depth and a radial axis extending perpendicularly from the longitudinal axis;
b) at least two continuous reamer blades, each reamer blade comprising a blade length extending from a proximal blade end adjacent to the proximal body end to a distal blade end adjacent to the distal body end, wherein each reamer blade comprises a reamer blade attachment portion and a reamer blade cutting portion partitioned between the proximal and distal blade ends by a reamer blade transition line that extends along the reamer blade length, each reamer blade is bent at an angle along the transition line such that the blade cutting portion and the blade attachment portion are not coplanar; and
c) wherein the reamer blades are positioned about the body, spaced apart from each other by a blade separation distance with a blade separation area therebetween, such that the reamer blade attachment portion is positioned within its respective body slot, the reamer blade cutting portion extending outwardly from the outer surface of the body.
18. The reamer head assembly of claim 17 wherein the blade separation distance ranges from about 0.3 mm to about 15.0 mm.
19. The reamer head assembly of claim 17 wherein the blade separation area is defined by:
[
Cavity
Cross
Sectional
Area
-
Reamer
Cross
Sectional
Area
]
Number
of
Reamer
Blades
wherein the cavity cross sectional area is equal to a cross sectional area of a cavity within a bone formed by the reamer head assembly, and the reamer cross sectional area is the combined cross sectional areas of the body and the reamer blades.
20. The reamer head assembly of claim 17 wherein the first slot angle ranges from about 5° to about 30° and the second slot angle ranges from about 5° to about 45°.
21. The reamer head assembly of claim 17 wherein each reamer blade has a relief angle that ranges from about 1° to about 25° and a rake angle that ranges from about 5° to about 25°.
22. A reamer head assembly comprising:
a) a body comprising an annular outer surface, a proximal body end extending to a distal body end along a longitudinal axis, at least two body slots, each slot having a slot length and a slot depth positioned within the annular outer surface of the body such that the slot length is not parallel with the longitudinal axis as it extends from the proximal body end to the distal body end, the slot depth penetrating through a portion of the outer surface of the body, each body slot further comprising a first slot angle and a second slot angle, the first slot angle measured between the slot length and the longitudinal axis, the second slot angle measured between the slot depth and a radial axis extending perpendicularly from the longitudinal axis;
b) at least two continuous reamer blades, each reamer blade comprising a reamer blade attachment portion and a reamer blade cutting portion partitioned therebetween by a reamer blade transition line that extends along a reamer blade longitudinal axis;
c) each reamer blade positioned about the cylindrical body, spaced apart from adjacent reamer blades by a blade separation distance and a blade separation area therebetween, such that the reamer blade attachment portion is positioned within its respective body slot; and
d) wherein each reamer blade is bent at an angle along the reamer blade transition line such that the reamer blade cutting portion and the reamer blade attachment portion are not coplanar.
23. The reamer head assembly of claim 22 wherein the angle between the reamer blade attachment portion and the blade cutting portion is about 85° to about 175°.
24. The reamer head assembly of claim 22 wherein the blade separation distance ranges from about 0.3 mm to about 15.0 mm.
25. The reamer head assembly of claim 22 wherein the blade separation area is defined by:
[
Cavity
Cross
Sectional
Area
-
Reamer
Cross
Sectional
Area
]
Number
of
Reamer
Blades
wherein the cavity cross sectional area is equal to a cross sectional area of a cavity within a bone formed by the reamer head assembly and the reamer cross sectional area is the combined cross sectional areas of the body and the reamer blades.
26. The reamer head assembly of claim 22 wherein the first slot angle ranges from about 5° to about 30° and the second slot angle ranges from about 5° to about 45°.
27. The reamer head assembly of claim 22 wherein each reamer blade has a relief angle that ranges from about 1° to about 25° and a rake angle that ranges from about 5° to about 25°.
28. The reamer head assembly of claim 22 wherein a bone cutting surface resides between the forward cutting surface and the rearward cutting surface, the bone cutting surface further positioned such that it faces toward the distal end portion of the reamer head assembly.
29. The reamer head assembly of claim 1 wherein the annular outer surface of the body is cylindrical.
30. The reamer head assembly of claim 1 wherein the reamer blade cutting portion has a helical shape from the proximal blade end to the distal blade end.