Morse taper

• US 4,787,907 A
• Filed: 02/03/1987
• Issued: 11/29/1988
• Est. Priority Date: 02/03/1987
• Status: Expired due to Fees

• Current Assignee: Techmedica, Inc.
• Original Assignee: Techmedica, Inc.
• Inventors: Carignan, Roger G.
• Primary Examiner(s): Apley, Richard J.
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US07/010,473
• Time in Patent Office: 665 Days
• Field of Search: 403/16, 403/354, 403/361, 403/334, 403/356, 128/92 YZ, 623/22, 623/23, 623/16-21
• US Class Current: 623/23.44
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• CPC Class Codes: A61F 2/4603 for insertion or extraction of endoprosthetic joints or of accessories thereof
• CPC Class Codes: A61F 2/4637 for connecting or disconnecting two parts of a prosthesis
• CPC Class Codes: A61F 2002/2825 Femur
• CPC Class Codes: A61F 2002/30154 square
• CPC Class Codes: A61F 2002/3021 frustoconical
• CPC Class Codes: A61F 2002/30214 having tapered sections of different conicities
• CPC Class Codes: A61F 2002/30331 made by longitudinally pushing a protrusion into a complementarily-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2002/30332 Conically- or frustoconically-shaped protrusion and recess
• CPC Class Codes: A61F 2002/30392 Rotation
• CPC Class Codes: A61F 2002/3055 for adjusting length
• CPC Class Codes: A61F 2002/30878 with non-sharp protrusions, for instance contacting the bone for anchoring, e.g. keels, pegs, pins, posts, shanks, stems, struts
• CPC Class Codes: A61F 2002/30909 Nets
• CPC Class Codes: A61F 2002/30975 made of two halves
• CPC Class Codes: A61F 2002/4641 for disconnecting
• CPC Class Codes: A61F 2220/0025 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/0033 made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2230/0021 square
• CPC Class Codes: A61F 2230/0067 conical
• CPC Class Codes: A61F 2310/00407 Coating made of titanium or of Ti-based alloys

Abstract

An improved Morse taper consisting essentially of a male taper and a mating female taper, one of the tapers having a key recess at the periphery of a mating face such that a key can be inserted and rotated to force the segments longitudinally apart from its assembled embodiment such tapers are particularly useful in skeletal structures. A distraction key with a cam designed to fit in and rotate in the key recess is also described.

Claims

1. An improved orthopedic taper joint for holding two bones together comprising two segments, one segment having a cylindrical male taper narrower at its connecting end and the other segment having a mating female taper wider at its connecting end, each segment having a face around the taper such that said faces are opposing when said segments are assembled, wherein a recess is located on the periphery of one of said faces such that a rotatable key can be inserted and rotated to force said segments longitudinally apart to disconnect the two bones held together, and wherein an interfitting lug is positioned on the face opposite the face defining said recess, said lug being substantially the width of said recess, but shorter than the depth of said recess, causing the formation of a slot between the end of the lug and the bottom of said recess when assembled, and wherein said rotatable key has a cam mounted on one end of a handle, wherein said cam is sized to fit within said slot and is rotatable therein, and wherein said segments have retaining wire mesh sections along the sides of said segments to allow tissue and bone to grow into said wire mesh sections and securely affix said structure to the bones to be joined.

2. An improved orthopedic taper structure as claimed in claim 1, wherein said segments have extending ends having flattened sides which are received and held with the ends of the bones to be joined by the taper structure.

3. An improved orthopedic taper structure as claimed in claim 2, wherein said segments have exposed slots on the exterior sides of said segments.

4. A bone joint comprising the combination:

a first segment having an extending portion to be received within a bone cavity and terminating in an enlarged head portion having an inner set depending taper narrowest at its terminus; and

a second segment having an extending portion to be received within a bone cavity and having an opposed enlarged head portion having a recess adapted to receive said inner set depending taper in mating engagement, one of said enlarged head portions having a slot for receiving a tool such that upon rotation of said tool longitudinal forces are imparted to each of said first and second segments to separate the same.