Process for fusing bone joints

• US 4,501,269 A
• Filed: 02/21/1984
• Issued: 02/26/1985
• Est. Priority Date: 12/11/1981
• Status: Expired due to Term

• Current Assignee: Zimmer Spine, Inc. (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Washington State University
• Inventors: Bagby, George W.
• Primary Examiner(s): Apley, Richard J.
• Assistant Examiner(s): Isabella, David
• Application Number:
  US06/581,841
• Time in Patent Office: 371 Days
• Field of Search: 128/92 G, 128/92 CA, 128/92 C, 128/92 B, 128/92 BA, 3/1, 3/1 G, 3/1 GI
• US Class Current: 606/279
• CPC Class Codes: A61B 17/68 Internal fixation devices , including fasteners and spinal fixators, even if a part thereof projects from the skin bone staples A61B17/0642
• CPC Class Codes: A61D 1/00 Surgical instruments for veterinary use
• CPC Class Codes: A61F 2/4202 for ankles
• CPC Class Codes: A61F 2/442 Intervertebral or spinal discs, e.g. resilient non-disc-shaped intervertebral inflatable pockets A61F2/441; non-disc-shaped intervertebral fusion implants A61F2/4455
• CPC Class Codes: A61F 2/446 having a circular or elliptical cross-section substantially parallel to the axis of the spine, e.g. cylinders or frustocones
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2002/2835 Bone graft implants for filling a bony defect or an endoprosthesis cavity, e.g. by synthetic material or biological material
• CPC Class Codes: A61F 2002/30235 tubular, e.g. sleeves
• CPC Class Codes: A61F 2002/30593 hollow
• CPC Class Codes: A61F 2002/30622 Implant for fusing a joint or bone material
• CPC Class Codes: A61F 2002/30785 parallel
• CPC Class Codes: A61F 2002/30787 inclined obliquely with respect to each other
• CPC Class Codes: A61F 2230/0069 cylindrical

Abstract

A process for immediate stabilization and subsequent promotion of bone-to-bone fusion in a joint where separation of the bones is restricted by surrounding ligaments or other soft tissue. A hole is bored transversely across the joint. A slightly larger cylindrical basket is driven into the hole, thereby spreading the bones in resistance to the tensile forces of the surrounding tissue. Immediate stabilization of the joint is achieved by the implantation of the rigid cylindrical basket. Subsequent bone-to-bone fusion is achieved, both through and about the basket, which is filled with bone fragments produced during the boring step.

Claims

1. A process for stabilizing and promoting bone-to-bone fusion of a human or animal joint such as a spinal joint between adjacent vertebrae or the ankle joint formed by opposed contiguous bony surfaces which are covered and separated by intervening cartilage and are surrounded by ligaments which resist expansion of the joint;

comprising the following steps;

surgically accessing the joint;

removing intervening cartilage located between the contiguous bony surfaces;

boring across the contiguous bony surfaces a transverse cylindrical opening having a selected inside diameter about opposed semi-cylindrical surface areas formed across the respective bony surfaces;

retaining the fresh autogenous bone fragments produced by the boring step;

driving into the transverse cylindrical opening a hollow basket having a rigid perforated cylindrical wall whose outside diameter is slightly greater than the inside diameter of the cylindrical opening to immediately stabilize the joint by spreading the bony surfaces apart in opposition to the resistance to expansion of the joint provided by the surrounding ligaments;

filling said hollow basket with fresh autogenous bone fragments produced by the boring step, thereby omitting the need for a second surgical site, to promote bone ingrowth about the basket and through its perforated cylindrical wall while providing immediate stabilization of the joint; and

closing the access to the joint.

2. A process for stabilizing and promoting fusion of a human or animal joint as claimed in claim 1, further comprising the following steps:

attaching an implant tool to the bone cage before driving it into the cylindrical opening;

applying impact to an end of the tool to drive the bone cage within the cylindrical opening; and

removing the tool from the bone cage after driving the bone cage into the cylindrical opening.

3. A process for stabilizing and promoting fusion of a human or animal joint as claimed in claim 1, wherein the difference in diameter between the inside diameter of the cylindrical opening and the outside diameter of the bone cage is approximately two millimeters.