Femoral neck compression screw system with ortho-biologic material delivery capability

• US 7,118,572 B2
• Filed: 01/27/2004
• Issued: 10/10/2006
• Est. Priority Date: 02/03/2003
• Status: Expired due to Fees

• Current Assignee: Orthopedic Designs, Inc.
• Original Assignee: Orthopedic Designs, Inc.
• Inventors: Bramlet, Dale G., Sterghos, Peter M.
• Primary Examiner(s): Robert, Eduardo C.
• Assistant Examiner(s): DAVIS, DANIEL J
• Application Number:
  US10/766,666
• Publication Number:
  US 20040193162A1
• Time in Patent Office: 987 Days
• Field of Search: 606/73, 606/232
• US Class Current: 606/66
• CPC Class Codes: A61B 17/7098 wherein the implant is permeable or has openings, e.g. fenestrated screw hollow surgical screws A61B17/864
• CPC Class Codes: A61B 17/746 the longitudinal elements coupled to a plate opposite the femoral head
• CPC Class Codes: A61B 17/8888 at its central region

Abstract

This device addresses the treatment of femoral neck trauma which includes basilar, mid-cervical and sub-cap fractures. The assembly has a lag screw assembly, side plate, compression screw and cortical screw, which are implantable. A syringe adaptor instrument delivers ortho-biologic material to the fracture site through the lag screw assembly. The lag screw assembly utilizes a cannulated screw with external threads and deployable tangs to anchor into the femoral head and is implanted in such a manner as to have the lag screw threads and tangs located on the opposite side of the fracture from the side plate. The distal shaft of the lag screw interfaces with the side plate in a manner which allows axial translation only. To deliver ortho-biologic material to the fracture site, the syringe adaptor instrument is inserted into the cannulated lag screw prior to the installation of the compression screw and the material is forced through it and out exit holes located circumferentially around the lag screw between the fracture site and the deployable tangs.

Claims

1. A compression screw assembly for delivery of an ortho-biological material to a fracture site comprising a lag screw, a side plate, an elongated adapter, and a compression screw, said lag screw having an elongated body with a leading end, a distal end, and a longitudinal bore, external threads on said leading end for engaging a bone proximal to a fracture site, said leading end of said lag screw having at least one tang exit hole, a tang body movably disposed in said longitudinal bore and having at least one tang leg mounted to a first end, said tang leg adapted to translate through said at least one tang exit hole upon movement of said tang body, and a second end of said tang body having internal screw threads adapted to seal said tang body, said distal end of said lag screw adapted to extend distally of said fracture site, a first connector on said distal end, at least one discharge hole in said elongated body between said external threads and said distal end, said side plate having a body with a distal surface and a proximal surface, an aperture in said plate sized to accommodated said distal end of said lag screw whereby said side plate is adapted to slide along said elongated body and exerts compressive force between an enlarged head and said external threads, said adapter being of a size to telescope within said through bore of said elongated body, said elongated adapter having a bore extending from one end and terminating in a fluid exit port near the other end, said other end beyond said fluid exit port having external screw threads adapted to engage said internal screw threads in said tang body, said one end adapted to be connected with a syringe and said fluid exit port adapted to register with said discharge hole in said elongated body whereby ortho-biological material may be delivered to a fracture site, said compression screw having said enlarged head on one end and a second connector on the other end, said second connector on said compression screw adapted to mate with said first connector whereby said compression screw exerts a compressive force between said enlarged head and said external threads reducing the fracture.

2. A compression screw assembly of claim 1 comprising said distal end of said elongated body shaped for non-rotational movement and said aperture shaped for sliding longitudinally along said body.

3. A compression screw assembly of claim 2 comprising a barrel on said proximal surface of said side plate surrounding said aperture.

4. A compression screw assembly of claim 1 comprising a barrel on said proximal surface of said side plate surrounding said aperture.

5. A compression screw assembly of claim 4 comprising a cortical screw hole in said side plate.

6. A compression screw assembly of claim 1 comprising a cortical screw hole in said side plate.

7. A compression screw assembly kit for delivery of an ortho-biological material to a fracture site comprising a lag screw, a compression screw, a side plate, and an adapter, said lag screw having external threads and at least one tang exit hole at one end adapted to fix said lag screw in a bone proximal to a fracture site, a bore extending from said one end to the other end, said bore having internal threads in said other end, a circumferential seal in said bore spaced distally from said external threads, a discharge hole in said bore between said external threads and said other end, said side plate having an aperture adapted to telescope with said other end of said lag screw, said adapter having one end, a connector on the other end and a bore from said connector terminating in a fluid exit port near said one end, said adapter having a circumferential shoulder between said fluid exit port and said connector, a movable tang body in said bore between said discharge hole and said external threads, said tang body having at least one tang lea on one end and a seal on the other end, said one end of said adapter sized to engage said seal on said tang body whereby upon insertion of said adapter into said lag screw said one end of said adapter engages said seal in said tang body and said tang body is moved within said bore to register said fluid exit port and said discharge hole thereby extending said tang leg from said tang exit hole, said compression screw having an enlarged head on one end and external threads on the other end, said connector sized to pass through said aperture of said side plate and engage said internal threads in said through bore of said lag screw, said head adapted to engage said body of said side plate, whereby said lag screw may be threadably fixed in a bone proximal to a fracture site, said adapter is insertable into said lag screw with said shoulder engagable with said seal and said fluid exit port registered with said discharge hole, said connector adapted to mate with a source of ortho-biological material for permitting said ortho-biological material to flow through said adapter and out the discharge hole in the vicinity of said fracture site, said adapter being removable, said side plate adapted to be telescoped with said lag screw and said compression screw being insertable through said aperture for threadable engagement with said internal threads to apply compressive force between said side plate and said lag screw to reduce said fracture.

8. A compression screw assembly kit of claim 7 comprising said seal in said tang body being threads, said one end of said adapter having threads whereby threadably engaging said adapter threads and said tang body threads forms a seal.

9. A compression screw assembly for reduction of a fracture comprising a lag screw, an adapter, and a compression screw, said lag screw having an elongated body with a leading end, a distal end, and a longitudinal bore, external threads on said leading end for engaging a bone proximal to a fracture site, a tang body movably mounted in said longitudinal bore, said tang body having at least one tang leg, at least one tang exit hole formed in said leading end communicating with said longitudinal bore, said adapter sized to telescope through said longitudinal bore and engage and move said tang body toward said leading end and said tang leg extends through said tang exit hole as said tang body is moved toward said leading end, said adapter having a bore extending from one end and terminating in a fluid exit port near the other end, said distal end of said lag screw adjustably connected to one end of a compression screw having an enlarged head on the other end, said compression screw adapted to adjust the interval between said external threads and said enlarged head whereby said compression screw exerts a compressive force between said enlarged head and said external threads reducing the fracture.

10. A compression screw assembly of claim 9 comprising an end cap mounted in said leading end of said longitudinal bore.