Stabilizer for the treatment of the fracture of the neck and upper metaphysis of the femur

• US 4,964,403 A
• Filed: 12/15/1987
• Issued: 10/23/1990
• Est. Priority Date: 12/19/1986
• Status: Expired due to Fees

• Current Assignee: HUTA BAILDON PRZEDSIEBIORSTWO PANSTWOWE, KATOWICE, UL. ZELAZNA 9, POLAND
• Original Assignee: Huta Baildon Przedsiebiorstwo Panstwowe Katowice
• Inventors: Ramotowski, Witold, Tuziemski, Aleksander, Cieplak, Jerzy, Granowski, Robert, Karas, Wlodzimierz, Pilawski, Kazimierz
• Primary Examiner(s): Apley, Richard J.
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US07/132,937
• Time in Patent Office: 1,043 Days
• Field of Search: 623/16, 128/92 Z, 128/92 ZZ, 128/92 ZK, 128/92 ZW, 128/92 YV, 128/92 YP, 128/92 YG, 128/92 YF, 128/92 YE, 128/92 YL
• US Class Current: 606/60
• CPC Class Codes: A61B 17/746 the longitudinal elements coupled to a plate opposite the femoral head
• CPC Class Codes: A61B 17/8014 the extension or compression force being caused by interaction of the plate hole and the screws
• CPC Class Codes: A61B 17/8028 Cushions, i.e. elements forming interface between bone plate and bone
• CPC Class Codes: A61B 17/8033 having indirect contact with screw heads, or having contact with screw heads maintained with the aid of additional components, e.g. nuts, wedges or head covers
• CPC Class Codes: A61B 17/8047 wherein the additional element surrounds the screw head in the plate hole A61B17/8052 takes precedence
• CPC Class Codes: A61B 17/86 Pins or screws or threaded wires; nuts therefor A61B17/72 take precedence

Abstract

A stabilizer for the treatment of the fractures of the neck and the upper metaphysis of the femur. The stabilizer plate 1 has a groove 2 in its bottom part and bent between tapered holes 3 passing into oval holes at their lower parts and tapered holes 4 passing into round holes at their lower part at an angle such that, after bone bolts 8 are secured in the porous bone fragments, the angle between them and plate 1 is approximately the same as that formed between the neck and shaft of the bone. The bolts 8 have a high pitch cortex thread 9 at the end of a cylindrical core, the latter having an enlarged part 12 on the opposite side and of the same width as that of groove 2 and terminating in a protruding shank 13 with a machine thread, while bolts 5 each have an enlarged disc-like part 7 disposed between the cortex and machine threads and having a width equal to that of groove 2, and conical-shaped nuts 14 are screwed on to protruding shanks 6 and 13.

Claims

1. A stabilizer for the treatment of fractures of a femur neck and the proximate upper metaphysis of the femur, comprising:

an elongated bent plate having a planar base and an upper angularly disposed arm, the plate being adapted to be mounted by means of bone screws and fasteners adjacent the neck and proximate upper portion of a fractured femur, characterized in that the plate is provided with a first set of holes having on the side of the plate away from the bone a frusto-conical tapered shape, while on the side of the plate facing the bone an oval shape, and a second set of holes in the upper angular arm portion of the plate having on the side facing away from the bone a frusto-conical tapered shape and on the side adjacent the bone a circular shape, there being an elongated groove along the entire length of the plate on the side to face toward the bone, a first set of bone bolts adapted to be secured in the base of the femur in the upper proximate region near the fracture, said bolts having cortex-type high pitch threads for securing the same within the porous structure of the bone itself, there being a second set of elongated bolts adapted to be secured in the neck portion of the femur, said second set of bolts having cortex-type high pitch threaded portion at the leading ends thereof, and having an intermediate cylindrical unthreaded core adapted to pass through corresponding cylindrical holes pre-drilled in the neck portion of the femur and having at the remote outer ends, threaded shank portions adapted to be secured by means of fastener nuts to said plate arm, said second set of bolts having at least one cutting-edge extending around the lead end of said cortex thread part, to enable securing said bolts into the femur neck without pretapping holes in any bone fragments, both of said sets of bolts having second threaded shank portions at the remote head ends thereof in the form of a standard machine threads adapted to protrude outwardly through the sets of plate holes, said bolts further being provided with a disc in the form of an enlarged shoulder between the intermediate core and threaded outer shank, adapted to fit within said elongated groove in the plate upon assembly therewith, the remote threaded shank ends of said bolts extending through said sets of holes to be secured to the plate by means of corresponding sets of fastener nuts having internal threaded portions to match the threads on said protruding bolt shanks, and frusto-conical tapered base parts corresponding to the tapered holes in said plate, whereupon selective tightening of said fastener nuts over said stabilizer plate will enable deformation of said plate to apply appropriate tension forces to said elongated bone bolts without exertion of any adverse pressure by the plate against the bone.

2. A stabilizer according to claim 1, wherein said high pitch cortex thread portion on each of the second set of bone bolts adjacent said cylindrical core portion there is provided a self-cutting edge to facilitate removal.

3. A stabilizer according to claim 1, wherein the fastener nut has, in addition to said frusto-conical base part, a cylindrical center and a square-shaped top portion with truncated corners corresponding to the diameter of the cylindrical center part.