Z-shaped boneplate and the method for internal fixation of long bone fractures and allograft materials

• US 5,133,718 A
• Filed: 03/28/1990
• Issued: 07/28/1992
• Est. Priority Date: 04/30/1989
• Status: Expired due to Fees

• Current Assignee: Zhang Mao
• Original Assignee: Zhang Mao
• Inventors: Mao, Zhang
• Primary Examiner(s): Hafer, Robert A.
• Assistant Examiner(s): ROONEY, KEVIN
• Application Number:
  US07/500,589
• Time in Patent Office: 853 Days
• Field of Search: 606/60, 606/62, 606/69-71, 606/72
• US Class Current: 606/281
• CPC Class Codes: A61B 17/80 Cortical plates , i.e. bone plates; Instruments for holding or positioning cortical plates, or for compressing bones attached to cortical plates

Abstract

The present invention provides a kind of boneplate for fixation of long bone fracture and allograft materials in humans and mammals. It is a Z-shaped boneplate, which fixes the fractured bone internally by inserting the boneplate into the boneslot. A Z-shaped boneplate is made up of an upper flange member and a lower flange member and both related to a web member. Its cross section is a Z-section beam. The surgical procedure concerning this invention mainly involves cutting a proper boneslot and inserting the boneplate into the boneslot, thus making the upper and lower flanges abut the inner and outer cortexes respectively and avoid bending and torsion between the fractured ends and any displacement between the cross sections of the fractured ends, therefore, provide stable locking of the fractured ends.

Claims

1. A boneplate for fixation of long bone fractures and allograft materials in humans and mammals comprising:

an upper flange member, a lower flange member and a web member connecting the upper and lower flange members, the upper flange member and lower flange member each extending from opposite ends of the web and in opposite directions transverse to the web member to form a boneplate which is Z-shaped in cross section.

2. The boneplate as defined in claim 1, wherein the upper and lower flanges are parallel to each other.

3. The boneplate as defined in claim 1, wherein the upper and lower flanges extend from the web member at a right angle.

4. The boneplate as defined in claim 1, wherein a tail flange member extends form the lower flane member and is shaped to conform to the internal contour of a hollow bone together with the lower flange member.

5. The boneplate as defined in claim 1, wherein the web member contains at least one aperture.

6. A method of inserting a Z-shaped boneplate in a boneslot for internal fixation of long bone fractures, the method comprising the steps of:

a) providing a Z-shaped boneplate as defined in claim 1;

b) exposing and reducing the bone at the are of the fracture;

c) cutting a slot in the bone transverse to and spanning two fracture ends of the bone;

d) inserting the web member and the Z-shaped boneplate provided in step (a) in the slot made in one fracture segment of the bone;

e) approximating two fractured ends so as to align the bone and slot;

f) driving the Z-shaped boneplate along the slot and across the area of the fracture so that the Z-shaped boneplate spans and fixes the two sides of the fractured bone with the boneplate contained in each fracture segment of the bone.

7. The method of claim wherein step (c) further comprises the steps of:

a) clamping the two fractured ends of the bone in aligned and reduced condition;

b) scoring a substantially straight line spanning the fracture longitudinally along the bone surface with the length of the portion f the line on one side of the fracture being at least equal to the length of the boneplate and the length of the portion of the line on the other side of the fracture being approximately half the length of the boneplate;

c) cutting a slot in the bone along the line scored on the bone, the width of the slot being equal to the thickness (T) of the Z-shaped boneplate.