Spinal fixator

• US 4,401,112 A
• Filed: 10/02/1981
• Issued: 08/30/1983
• Est. Priority Date: 09/15/1980
• Status: Expired due to Term

• Current Assignee: Seyed M. Rezaian
• Original Assignee: Seyed M. Rezaian
• Inventors: Rezaian, Seyed M.
• Primary Examiner(s): FRINKS, RONALD
• Application Number:
  US06/308,016
• Time in Patent Office: 697 Days
• Field of Search: 128/92 R, 128/92 B, 128/92 C, 128/92 D, 128/92 E, 128/84 R, 128/92 G, 128/69, 128/75, 128/78, 3/1.9, 3/1.91
• US Class Current: 606/279
• CPC Class Codes: A61B 17/0642 for bones, e.g. for osteosynthesis or connecting tendon to bone
• CPC Class Codes: A61B 17/7059 Cortical plates A61B17/7007, A61B17/7058 take precedence
• CPC Class Codes: A61B 17/8061 specially adapted for particular bones A61B17/70 and A61B17/74 take precedence
• 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 2017/0641 having at least three legs as part of one single body
• CPC Class Codes: A61F 2/44 for the spine, e.g. vertebrae, spinal discs
• CPC Class Codes: A61F 2002/30411 having two threaded end parts connected by a threaded central part with opposite threads at its opposite ends, i.e. for adjusting the distance between both end parts by rotating the central part
• CPC Class Codes: A61F 2002/30507 using a threaded locking member, e.g. a locking screw or a set screw
• CPC Class Codes: A61F 2002/3055 for adjusting length
• CPC Class Codes: A61F 2002/30601 telescopic
• CPC Class Codes: A61F 2002/30777 Oblong apertures
• CPC Class Codes: A61F 2002/30841 Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2220/0025 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements

Abstract

A spinal fixator is in the form of a turnbuckle the end sections of which terminate as circular flat plates formed with upwardly and downwardly protruding spikes for engaging in the bone of respective vertebrae above and below a broken vertebra. Following decompression of the spinal cord, the fixator is inserted and extended to engage the spikes in the respective vertebrae and thereafter holds the spinal cord decompressed.

Claims

1. A spinal fixator, comprising:

first and second means having respective bearing portions for bearing against respective vertebral portions respectively above and below a broken vertebral portion and movable relative to each other,

adjusting means arranged to adjust the distance between said bearing portions for thereby setting the distance between said respective vertebral portions,

wherein said first and second means and said adjusting means are provided by upper and lower and intermediate sections, respectively, of a turnbuckle, and

a staple for bridging said respective vertebral portions, and

connecting means for connecting said staple to said intermediate section to prevent rotation of said intermediate section relative to said upper and lower sections and said staple.

2. A device according to claim 1, wherein said intermediate section is formed with approximately radial threaded holes for receiving a tommy bar, said connecting means comprises an externally threaded elongate element for screwing into one of the threaded holes, and said staple is formed with an aperture therethrough for closely receiving said element.

3. A device according to claim 1 further in which said connecting means is a screw held by said staple and operable to engage the intermediate section of said turnbuckle and prevent that section from rotating.

4. A device according to claim 3 further including a vertical slot in said staple whereby the vertical position of said screw may be varied.

5. A prosthetic spinal fixator for insertion between the lower face of a first vertebra portion and the upper face of a second vertebral portion that is below the first one comprising:

jacking means, composed of material suitable for bone surgery, for insertion directly between said upper and lower faces,

said jacking means having an upper end for engaging said lower face and a lower end for engaging said upper face and a rigid intermediate section adjustable to rigidly vary the distance between said upper and lower ends for thereby decompressing the spinal cord and setting the distance between said first and second vertebral portions,

said upper and lower ends having spike means for penetrating their complementary faces and each of said ends also having a surface that will be flush with its complementary face over a substantial area, said jacking means also having a height about equal to the height of a vertebral portion.

6. A prosthetic spinal fixator as defined in claim 5 in which said jacking means is a turnbuckle, said intermediate section being rotatable to vary said distance.

7. In a prosthetic spinal fixator as defined in claim 5, said jacking means comprising a turnbuckle which replaces a part of a broken vertebra and is comprised of upper, lower and intermediate sections aligned with the spinal cord in a substantially linear manner of which the upper and lower sections bear upwardly and downwardly against respective vertebral portions respectively above and below a broken vertebral portion and are movable relative to each other, and of which the intermediate section is adjustable to vary the distance between the upper and lower sections for thereby decompressing the spinal cord and setting the distance between said respective vertebral portions.

8. A device according to claim 5, including a U-shaped staple, longer than said jacking means, having means for penetrating the vertical sidewalls of the upper and lower vertebrae portions respectively to attach the staple to said portions.

9. In a device according to claim 8, said staple including means connecting the staple to said jacking means for maintaining the selected height of the jacking means.

10. The method of positioning spaced vertebral portions of the spinal cord, the upper one of the vertebral portions having a lower face, and the lower one of the vertebral portions having an uoper face, comprising:

inserting jacking means wholly within the space that is between said upper and lower faces and adjusting the height of the jacking means to provide decompression of the spinal cord and to also rigidly set the distance between said upper and lower faces.

11. The method of positioning spaced vertebral portions as defined in claim 10 which includes the step of preventing slippage between each end of the jacking means and its complementary vertebral face.

12. The method of positioning spaced vertebral portions as defined in claim 10 which includes effecting penetration of each end of the jack into its complementary face of a vertebral portion, whereby to prevent slippage.

13. The method of positioning spaced vertebral portions as defined in claim 12 which also includes connecting a staple to (a) a vertical side wall of the upper vertebral portion and also (b) a vertical side wall of the lower vertebral portion.

14. The method of positioning spaced vertebral portions as defined in claim 13 which also includes connecting the staple to the jacking means to maintain its position.