Abstract:
A spinal fixation apparatus consists of a connection means, a plurality of implant elements, washers and fastening elements. The implant elements are fastened to chines of the spine, and then the connection means is coupled on the upper side of the implant elements. Then corresponding washers and fastening elements are sequentially assembled. Finally the fastening elements are tightened on the implant elements to fasten the injured or ill-inflicted chines to the splint securely to form an integrated member to achieve a secure anchoring effect.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to a spinal fixation apparatus that is designed through mechanic analyses with shrunk component sizes and still has sufficient strength and fatigue durability, and is modularly designed to anchor an injured or ill-inflicted spine and is allowed to make across pitches and angular adjustments to splint the spine in an optimal condition to enhance mending and rehabilitating effect.  
         BACKGROUND OF THE INVENTION  
         [0002]    Many people living in modem time are used to sit or sleep at wrong postures, or do exercises the wrong ways, or run into accidents, and consequently suffer from spine injuries or ill-inflicted spine deterioration. The patients with spine injury usually have to take surgical operations to cure and mend the deformed spines. After surgery, the spine, whole or partial, usually is anchored by a splint for rehabilitation to help the patients restoring to normal conditions.  
           [0003]    Design of the splint for human spine has to take into account many factors, such as ergonomics, structural strength, and the like. The splint for spine generally has to be implanted inside human body to mend the injured or ill-inflicted chines. Based on different physical sizes of the patients, the splint has to be adjusted across pitches and angularly to make the splint fit smugly with the chines to achieve desired anchoring effect.  
           [0004]    In order to minimize inconvenience to patients&#39; movements, the dimensions of the splint should be as small as possible, and protrusion from the chines should also be minimized. While trying to reduce the size of the splint, the strength and fatigue durability of the splint should not be compromised to prevent the splint from breaking down or rupture, and to avoid the patients from suffering additional injury.  
           [0005]    In addition, human nerve systems are clustered around the rear side of the spine. Surgery for the spine and its surrounding areas is a very complex and delicate operation. To facilitate surgical operations, shorten operation time and enhance surgery safety, the splint for the spine and chines should be simplified with less number of components whenever possible.  
           [0006]    Moreover, different patients have different injured or ill-inflicted spine areas or chines. Hence design of the splint should have the flexibility for adjustments across the pitches and angularly to satisfy requirements of different conditions.  
         SUMMARY OF THE INVENTION  
         [0007]    The primary object of the invention is to resolve aforesaid problems and concerns. The invention provides a spinal fixation apparatus that can effectively reduce the protrusive height from the spine.  
           [0008]    Another object of the invention is to provide a spinal fixation apparatus with composing elements optimally designed through mechanic analyses to equip with sufficient strength and fatigue durability.  
           [0009]    A further object of the invention is to provide a spinal fixation apparatus that is composed of less number of anchoring elements and adopts an assembling and anchoring method which is done sequentially from down to top to make surgical operations simpler.  
           [0010]    Yet another object of the invention is to provide a spinal fixation apparatus that is adjustable across pitches and angularly.  
           [0011]    To achieve the foregoing objects, the splint of the invention includes a connection means, a plurality of implant elements, washers, and fastening elements. The connection means connects the implant elements, washers and fastening elements. The elements are adjustable across pitches and angularly. The fastening elements can fasten the implant elements tightly to completely anchor the injured or ill-inflicted spine or chines.  
           [0012]    The foregoing, as well as additional objects, features and advantages of the invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]    [0013]FIG. 1 is an exploded perspective view of the invention.  
         [0014]    [0014]FIG. 2 is an exploded sectional view of the invention.  
         [0015]    [0015]FIG. 3 is a schematic sectional view of the invention.  
         [0016]    [0016]FIG. 4 is a schematic view of a first embodiment of the invention.  
         [0017]    [0017]FIG. 5 is an exploded view of another type of a connection means of the invention.  
         [0018]    [0018]FIG. 6 is a fragmentary sectional view of another type of the connection means of the invention.  
         [0019]    [0019]FIG. 7 is a schematic view of a second embodiment of the invention.  
         [0020]    [0020]FIG. 8 is an exploded perspective view of another type of the implant element and fastening element of the invention.  
         [0021]    [0021]FIG. 9 is an exploded sectional view of another type of the implant element and fastening element of the invention.  
         [0022]    [0022]FIG. 10 is a schematic view of a third embodiment of the invention. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0023]    Referring to FIG. 1, the splint according to the invention consists of a plurality of implant elements  1 , washers  3 , fastening elements  4  and a connection means  2 .  
         [0024]    The implant elements  1 , connection means  2 , washers  3 , and fastening elements  4  may be integrally formed or fabricated.  
         [0025]    The implant elements  1  and connection means  2  are optimally designed through mechanic analyses to equip with sufficient strength and fatigue durability.  
         [0026]    Referring to FIGS. 2 and 3, the implant element  1  is a rod having one end formed implant screw threads  11  for a selected length to fasten to a chine  8 . The implant screw threads  11  may be formed in a conical shape to reduce fastening resistance. The implant element  1  has another end opposite to the implant screw threads  11  forming external fastening screw threads  12 . There is a jutting ring  13  located between the implant screw threads  11  and external fastening screw threads  12 . The jutting ring  13  has a plurality of tangent surfaces formed on the peripheral surface thereof for receiving force to turn the implant element  1 . The jutting ring  13  has one side formed a spherical surface  6  facing the external fastening screw threads  12 .  
         [0027]    The connection means  2  is a narrow plank with two parallel planes and a plurality of slots  21  of a selected length formed longitudinally therein normal to the planes for coupling with the external fastening screw threads  12  of the implant element  1 . The slot  21  and the peripheral edges of the external fastening screw threads  12  have a selected allowance formed therebetween to allow the implant element  1  making angular adjustments desired.  
         [0028]    The slot  21  has two sides facing the two planes. At least one of the sides has a plurality of spherical concave surfaces  22  formed thereon to allow the implant element  1  running through the slot  21  to adjust position and angle according to the location and direction of the chine  8 .  
         [0029]    When both sides of the slot  21  have the spherical concave surfaces  22  formed thereon, the spherical concave surfaces  22  on both sides are corresponding to one another.  
         [0030]    When only one side of the slot  21  has the spherical concave surfaces  22  formed thereon, the implant element  1  may have a bigger angular adjustment range.  
         [0031]    When the connection means  2  is assembled, it can be bent in an arched shape according to the form of the chine  8 .  
         [0032]    The washer  3  has an aperture  31  of a selected size formed in the center thereof to couple with the external fastening screw threads  12  run through the slot  21 . -The aperture  31  and the peripheral edges of the external fastening screw threads  12  have a selected allowance formed therebetween to allow the implant element  1  making angular adjustments desired. When one side of the connection means  2  is formed with the spherical surface  6 , another side opposite to the spherical surface  6  may be formed with a fastening plane  7 .  
         [0033]    The spherical concave surfaces  22  of the connection means  2  has same spherical curvature as the spherical surface  6  of the implant element  1  and washer  3 . Hence the implant element  1  may be adjusted angularly relative to the connection means  2  according to the location and direction of the chine  8 .  
         [0034]    The fastening element  4  is a strut element having a plurality of tangent surfaces to receive force for turning, and has a screw bore  41  in the center to engage with the external fastening screw threads  12  of the implant element  1 . The fastening element  4  has a plane  7  formed on one side thereof facing the washer  3 .  
         [0035]    Referring to FIG. 4 for a first embodiment of the invention, a plurality of the implant elements  1  are screwed and fastened to chines  8  of the spine through the implant screw threads  11 . Then sequentially assemble the connection means  2 , washer  3  and fastening element  4  through the external fastening screw threads  12  of the implant elements  1 . Finally the fastening element  4  is tightened to anchor the implant element  1 , washer  3  and fastening element  4  through the connection means  2 . Thus the injured or ill-inflicted chines  8  can be integrally fastened to the splint to achieve a secure anchoring.  
         [0036]    Referring to FIGS. 5 and 6 for another type of the connection means which consists of a plurality of connection elements  51 , a rod  52  of an uniform cross section and a plurality of set screws  53 .  
         [0037]    The connection element  51  is an elongated plank having two parallel planes which have one end forming a first aperture  511  normal to the planes for coupling with the external fastening screw threads  12  of the implant element  1 . The first aperture  511  and the peripheral edges of the external fastening screw threads  12  have a selected allowance formed therebetween to allow the implant element  1  making angular adjustments desired. The first aperture  511  has two ends facing the parallel planes and forming respectively a spherical and annular concave rim  512 . The connection element  51  has another end opposing to the first aperture  511  and forming a second aperture  513  therein in parallel with the parallel planes. The second aperture  513  is bordered with a jutting side which has another plane with a set screw hole  514  formed therein to run through the another plane to communicate with the second aperture  513 .  
         [0038]    The spherical and annular concave rim  512  has the same spherical curvature as the spherical surfaces  6  of the implant element  1  and washer  3 . Hence the implant element  1  may be adjusted angularly relative to the connection element  51  according to the location and direction of the chine  8 .  
         [0039]    The rod  52  of an uniform cross section may be modularly designed with different lengths to suit different pitches of the chines  8 .  
         [0040]    The set screw  53  is to engage with the set screw hole  514  for anchoring the rod  52  in the second aperture  513  on the connection element  5   1 .  
         [0041]    Referring to FIG. 7 for a second embodiment of the invention, a plurality of the implant elements  1  are screwed and fastened to chines  8  of the spine through the implant screw threads  11 . Then sequentially assemble the connection element  51 , washer  3  and fastening element  4  through the external fastening screw thread  12  of the implant element  1 . Finally the fastening element  4  and the set screw  53  are tightened to anchor the implant element  1 , connection element  51 , washer  3  and fastening element  4  through the rod  52 . Thus the injured or ill-inflicted chines  8  can be integrally fastened to the splint to achieve a secure anchoring.  
         [0042]    Referring to FIGS. 8 and 9 for another type of the implant element and fastening element, the implant element  1  is a rod having one end forming implant screw threads  11  for a selected length to fasten to the chine  8 . The implant screw threads  11  may be formed in a conical shape to reduce fastening resistance. The implant element  1  has another end opposite to the implant screw threads  11  forming external fastening screw threads  12  for a selected length. There is a jutting ring  13  located between the implant screw threads  11  and external fastening screw threads  12 . The jutting ring  13  has a plurality of tangent surfaces formed on the peripheral surface thereof for receiving force to turn the implant element  1 . The jutting ring  13  has one side formed a fastening plane  7  facing the external fastening screw threads  12 .  
         [0043]    The fastening element  4  is a strut element having a plurality of tangent surfaces to receive force for turning, and has a screw bore  41  in the center to engage with the external fastening screw threads  12  of the implant element  1 . The fastening element  4  has a spherical surface  6  formed on one side facing the connection means  2 .  
         [0044]    The spherical surface  6  of the fastening element  4  has same spherical curvature as the spherical concave surfaces  22  of the connection means  2 . Hence the implant element  1  may be adjusted angularly relative to the connection means  2  according to the location and direction of the chine  8 .  
         [0045]    Referring to FIG. 10 for a third embodiment of the invention, a plurality of the implant elements  1  are screwed and fastened to chines  8  of the spine through the implant screw threads  11 . Then sequentially assemble the washer  3 , connection means  2  and fastening element  4  through the external fastening screw threads  12  of the implant element  1 . Finally the fastening element  4  is tightened to anchor the implant element  1 , washer  3  and fastening element  4  through the connection means  2 . Thus the injured or ill-inflicted chines  8  can be integrally fastened to the splint to achieve a secure anchoring.