Acetabular cup extractor
An orthopedic instrument in the form of an acetabular cup extractor system for reliably and efficiently extracting an acetabular cup implant from an acetabulum. The system includes a handle assembly, an extractor attachable to a distal end of the handle, and a dome guide assembly having a hemi-spherical dome for engaging the extractor and a centering body extending distally from the hemi-spherical dome for engaging an acetabular implant. The extractor includes a curved, concave guide and a curved blade. The curved, concave guide is sized and shaped to substantially matingly engage with and cover a substantial portion of the hemi-spherical dome. As a result of such an arrangement, a uniform cut is achieved by the curved blade thereby resulting in a minimum of bone being extracted from the acetabulum around the acetabular cup implant during a surgical procedure.
1. An acetabular cup extractor system comprising:
a handle including:
an elongated shaft, and
a transverse handle extending substantially transverse to a longitudinal axis of the elongated shaft;
an extractor attachable to a distal end of the handle, the extractor including:
a guide, and
a blade; and
a dome guide assembly that includes:
a hemi-spherical dome for engaging the extractor, and
a centering body extending distally from the hemi-spherical dome for engaging an acetabular implant.
2. The acetabular cup extractor system of claim 1 , wherein the elongated shaft includes a strike plate about its proximal end.
3. The acetabular cup extractor system of claim 1 , wherein the transverse handle includes a first gripping handle at a first end of the transverse handle and a second gripping handle at a second end of the transverse handle opposite the first end.
4. The acetabular cup extractor system of claim 3 , wherein the first gripping handle has a longitudinal axis that extends transverse to a longitudinal axis of the second gripping handle.
5. The acetabular cup extractor system of claim 3 , wherein the second gripping handle includes a planar strike plate.
6. The acetabular cup extractor system of claim 5 , wherein the planar strike plate is a distally facing strike plate.
7. The acetabular cup extractor system of claim 3 , wherein the first gripping handle has a longitudinal axis substantially parallel to a longitudinal axis of the elongated shaft.
8. The acetabular cup extractor system of claim 1 , wherein the elongated shaft includes a fastener about its distal end for connecting to the extractor.
9. The acetabular cup extractor system of claim 1 , wherein the guide is a curved guide, or a concave guide.
10. The acetabular cup extractor system of claim 1 , wherein the blade is curved in both its longitudinal direction and in a widthwise extent transverse to the longitudinal direction.
11. The acetabular cup extractor system of claim 1 , wherein a tangency of a surface of a base of the blade is at a non-zero angle relative to the longitudinal axis of the elongated shaft.
12. The acetabular cup extractor system of claim 1 , wherein a portion of the blade extends beyond a plane defined by a side of the elongated shaft.
13. The acetabular cup extractor system of claim 1 , wherein the extractor includes a mount for engaging a fastener of the elongated shaft.
14. The acetabular cup extractor system of claim 13 , wherein the guide extends from the mount and the blade extends from the mount in a direction opposite the guide.
15. The acetabular cup extractor system of claim 1 , wherein the hemi-spherical dome includes:
a circular mount, and
a dome-like cap mounted to the circular mount.
16. The acetabular cup extractor system of claim 15 , wherein the circular mount includes a post and the dome-like cap includes a through hole for receiving the post.
17. The acetabular cup extractor system of claim 16 , wherein the post includes a fastener for connecting with the centering body, or wherein an overall height of the dome-like cap is greater than an overall height of the post.
18. The acetabular cup extractor system of claim 15 , wherein the dome-like cap has an overall width greater than an overall width of the circular mount.
19. The acetabular cup extractor system of claim 15 , wherein the dome-like cap is polymeric, or metallic with a low-friction coating.
20. The acetabular cup extractor system of claim 1 , wherein the centering body includes:
a sphere-like body; and
a fastener extending from the sphere-like body for connecting with the hemi-spherical dome.
21. The acetabular cup extractor system of claim 1 , wherein the centering body includes a pair of flats at its lateral sides.
22. The acetabular cup extractor system of claim 1 , further comprising a second extractor attachable to the distal end of the handle assembly, the second extractor including:
a finishing guide, and
a finishing blade having an overall length greater than the blade of the extractor.