Spinal fixation

• US 4,763,644 A
• Filed: 03/25/1986
• Issued: 08/16/1988
• Est. Priority Date: 02/28/1984
• Status: Expired due to Term

• Current Assignee: Biomet Merck Limited (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Peter J. Webb
• Inventors: Webb, Peter J.
• Primary Examiner(s): Sewell, Paul T.
• Assistant Examiner(s): Pham, Huong Q.
• Application Number:
  US06/843,561
• Time in Patent Office: 875 Days
• Field of Search: 128/68, 128/69, 128/92 B, 128/78, 128/92 D, 128/92 E
• US Class Current: 606/267
• CPC Class Codes: A61B 17/7032 Screws or hooks with U-shaped head or back through which longitudinal rods pass
• CPC Class Codes: A61B 17/809 with bone-penetrating elements, e.g. blades or prongs bone staples A61B17/0642; intramedullary nails with a plate at an end A61B17/7233
• CPC Class Codes: A61B 17/8695 Washers surrounding screw head in plate hole A61B17/8047, between bone plate and bone A61B17/8028
• CPC Class Codes: A61B 2090/037 with a frangible part, e.g. by reduced diameter

Abstract

A spinal scoliosis fixation implant comprises a plurality of devices which are associated with respective vertebrae and which are interconnected by a single semi-rigid wire, or by a cable with abutment ferrules. Each device may comprise a bone screw or hook with a slotted, externally threaded head into which is inserted the wire or cable and thereon a clamping element which projects slightly from the mouth of the slot, and a nut which is screwed onto the head to press the clamping element onto the wire or cable. The wire or cable can be unclamped, to permit adjustment of the device along the wire or cable, by simply untightening the nut.

Claims

1. A device for use in spinal fixation, comprising:

an elongate member, anchoring means for securing said device to a vertebra, and fixing means whereby said device is readily releasably fixed to said elongate member, said fixing means comprising first and second clamping elements which bear against respective transversely opposite sides of said elongate member and thereby clamp the elongate member between them, and readily releasable means which urges the clamping elements towards each other, said first clamping element being formed with a channel-shaped slot for receiving said elongate member, said slot having a mouth, said second clamping element projecting slightly out of the mouth of the slot in an assembled condition of the device, and said readily releasable means comprising a nut screwed onto said first clamping element to press said second clamping element against said elongate member.

2. A device for use in spinal fixation, comprising:

an elongate member, anchoring means for securing said device to a vertebra, and fixing means whereby said device is readily releasably fixed to said elongate member, said fixing means comprising first and second clamping elements which bear against respective transversely opposite sides of said elongate member and thereby clamp the elongate member between them, and readily releasable means which urges the clamping elements towards each other, said first clamping element being formed with a channel-slot for receiving said elongate member, said channel slot having a base, said second clamping element being connected by a very thin neck to a rod which extends away from the base of the slot.