Bone implants and cutting apparatuses and methods
Reamer sleeves, reamer assemblies, and methods of assembling the reamer assemblies are disclosed. The reamer sleeves include a base portion with a top surface and a bottom surface and a securement mechanism extending away from the top surface of the base portion. The securement mechanism includes an opening, at least one engagement member adjacent the opening, and at least one engagement protrusion extending away from the engagement member into the opening. The opening extends through the securement mechanism to the bottom surface of the base portion. The bone reamer assembly including a reamer and a reamer sleeve removably coupled to the reamer. The reamer including a shaft with a first and second end, a cutting member coupled to the second end of the shaft, and a groove near the second end of the shaft. A method of assembling a hard tissue reamer assembly is also disclosed.
1. A bone reamer assembly, comprising:
a bone reamer comprising:
a shaft with a proximal end and a distal end;
a cutting member coupled to the distal end of the shaft comprising a plurality of curved blades defining concave inner surfaces to enable cutting of a convex bone surface; and
an annular groove in the shaft positioned near the distal end of the shaft;
a reamer sleeve removably coupled to the annular groove of the reamer for protecting surrounding tissue from being cut by the reamer, wherein the reamer sleeve comprises:
a base portion having a top surface and a concave bottom surface, the base portion comprising:
a plurality of through openings extending from the top surface to the bottom surface, the plurality of through openings each including an edge, and wherein the edges are blunt; and
a securement mechanism extending away from the top surface of the base portion, the securement mechanism comprising:
a monolithic cylindrical body coupled to and extending away from the top surface of the base along a longitudinal axis and including an opening extending therethrough along the longitudinal axis to the bottom surface of the base portion, the cylindrical body comprising:
a solid collar portion defining a proximal end of the cylindrical body;
a solid distal ring portion defining a distal end of the cylindrical body;
at least one deformable member extending between the collar portion and the distal ring portion of the cylindrical body;
at least one aperture extending through the cylindrical body portion from an exterior surface thereof to the opening enclosed between the collar portion and the distal ring portion and adjacent to the at least one deformable member; and
at least one engagement protrusion extending from an interior surface of the least one deformable member into the opening to engage the annular groove in the shaft of the bone reamer to couple the reamer sleeve to the annular groove of the bone reamer,
wherein the plurality of through openings of the base portion are positioned circumferentially around the cylindrical body of the securement mechanism, wherein the top surface and the bottom surface of the base portion terminate at a peripheral rim, and wherein the peripheral rim is circumferential and has a smooth distal surface; and
an instrument including a coupling portion for receiving the proximal end of the bone reamer, wherein the coupling of the reamer sleeve to the annular groove at the distal end of the shaft adjacent to the cutting member allows for relative rotation of the reamer sleeve about a longitudinal axis of the shaft and prevents axial translation along the longitudinal axis of the shaft, and wherein the reamer sleeve rotates independent of the instrument and the bone reamer;
wherein the base portion of the reamer sleeve extends distally beyond an outer edge of a top surface of the cutting member.
2. The bone reamer assembly of claim 1 , wherein the reamer, further comprises:
a ring member positioned circumferentially around the shaft where the cutting member couples to the shaft.
3. The bone reamer assembly of claim 1 , wherein the collar portion extends circumferentially about the shaft of the bone reamer when the reamer sleeve and the bone reamer are coupled together.
4. The bone reamer assembly of claim 3 , wherein the base portion of the reamer sleeve is planar and angled as it extends away from the securement mechanism.
5. The bone reamer assembly of claim 3 , wherein the base portion is curved as it extends away from the securement mechanism.
6. The bone reamer assembly of claim 1 , wherein the securement mechanism removeably secures the reamer sleeve to the shaft of the reamer.
7. The bone reamer assembly of claim 1 , wherein the opening of the reamer sleeve is removably coupled to the shaft of the reamer and the opening on the bottom surface of the base portion is inserted over the proximal end of the shaft.
8. The bone reamer assembly of claim 1 , wherein the at least one aperture has a length and a width, the length extends along the longitudinal axis of the cylindrical body of the securement mechanism, and the length is larger than the width.
9. The bone reamer assembly of claim 1 , wherein the at least one engagement protrusion is positioned on the at least one deformable member near a midpoint of the length of the at least one aperture.
10. The bone reamer assembly of claim 1 , wherein the cylindrical body of the securement mechanism further comprises:
at least one side member extending between the collar portion and the distal ring portion of the cylindrical body; and
wherein the at least one deformable member and the at least one side member are positioned adjacent to and separated by the at least one aperture, and wherein the at least one deformable member and the at least one side member are recessed in from an exterior surface of the collar portion and an exterior surface of the distal ring portion.
11. The bone reamer assembly of claim 1 , wherein the at least one deformable member deforms when the engagement protrusion contacts the exterior surface of the shaft of the bone reamer until the engagement protrusion engages the annular groove in the shaft of the bone reamer preventing axial translation along the longitudinal axis of the shaft and allowing for relative rotation of the reamer sleeve.