Apparatus for removing pre-placed prosthetic joints

• US 5,222,958 A
• Filed: 03/25/1992
• Issued: 06/29/1993
• Est. Priority Date: 10/11/1988
• Status: Expired due to Fees

• Current Assignee: Linvatec Corporation (Jefferies Financial Group, Inc.)
• Original Assignee: Zimmer Incorporated (Zimmer Biomet Holdings, Inc.)
• Inventors: Chin, Albert K.
• Primary Examiner(s): ISABELLA, DAVID J
• Application Number:
  US07/857,138
• Time in Patent Office: 461 Days
• Field of Search: 606/99, 606/69, 606/73, 606/61, 606/86
• US Class Current: 606/99
• CPC Class Codes: A61B 17/1628 Motors; Power supplies
• CPC Class Codes: A61B 17/8847 for removing cement from a bone cavity using surgical bone chisels, drills, mills, rasps, reamers or scrapers A61B17/16; using laser A61B18/20; using ultrasonic surgical instruments A61N7/00
• CPC Class Codes: A61B 50/33 Trays
• CPC Class Codes: A61F 2/46 Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor
• CPC Class Codes: A61F 2/4607 of hip femoral endoprostheses
• CPC Class Codes: A61F 2002/4628 with linear motion along or rotating motion about an axis transverse to the instrument axis or to the implantation direction, e.g. clamping
• CPC Class Codes: A61F 2002/4681 by applying mechanical shocks, e.g. by hammering

Abstract

A method and apparatus for removing a pre-placed prosthetic joint from a bone cavity and conditioning the cavity for receipt of a replacement joint. The pre-placed joint is first pulled from the mantle of hardened cement holding it within the cavity, thus leaving a cavity within the mantle. A mass of fluid cement is then placed within the cement cavity, after which a pulling tool is inserted into the fluid cement and the fluid cement is permitted to cure to bond with the hardened cement and form an integral mass. The pulling tool has helical screw thread on it, with means to connect a slap-hammer to its proximal end, so that its insertion into the fluid cement defines a threaded passageway. The pulling tool is then partly removed from the passageway by unscrewing it. Tension is then applied to the pulling tool to remove the tool and the cement mantle surrounding it from the bone cavity. The tool is then reinserted and the process is repeated as many times as desired until all of the cement mantle is removed. Alternatively, multi-piece tools may be used so that when the tool is partly removed from the mantle, a portion of the tool remains behind for later use, thus saving the step of reinserting the tool.

Claims

1. A surgical pulling tool sized for embedment within a mass of cement disposed in a bone cavity to remove the cement from the bone cavity, said surgical tool comprising:

(a) a first rigid cylindrical post having proximal and distal ends, and having an exterior surface of a helical screw thread formed around said post;

(b) a second rigid cylindrical post attached to the distal end of said first post, said second post being of reduced diameter as compared to said first post and extending axially therefrom;

(c) means on said proximal section for securing a slap-hammer to said first post;

(d) wherein the second helical screw thread formed around said second post is of the same pitch as the helical screw thread formed around said first post.

2. A surgical pulling tool according to claim 1, wherein said first post comprises a proximal section and a distal section, and further comprising means for detaching said proximal section from said distal section.

3. A surgical pulling tool according to claim 2, wherein said means for detaching said proximal section from said distal section comprises:

(a) a cylindrical extension of smaller diameter than the post formed upon one said section of the post; and

(b) a recess for frictional receipt of said extension formed upon the other said section of the post.

4. A surgical pulling tool according to claim 1, further comprising means for detaching said second post from said first post.

5. A surgical pulling tool according to claim 4, wherein said means for detaching said second post from said first post comprises a recess in said first post which is threaded for receipt of said second post such that the posts may be detached by unscrewing said second post from said recess.