CROSS REFERENCE TO RELATED
This application is a divisional of U.S. patent application 5 Ser. No. 08/735,072, filed Oct. 18, 1996 now Pat. No. 6,171,311.
The present invention relates to transverse connectors 10 which generally include a pair of coupler bodies, each of the coupler bodies including a connecting mechanism for connecting each coupler body to a spinal rod for the purpose of interconnecting a pair of spinal rods. The present invention is a surgical tool or medical construct used with spinal rods 15 for the purpose of spinal fixation and correction of spinal curve.
BACKGROUND OF THE INVENTION
Spinal rods are often used for spinal fixation, often times 20 for correction of scoliotic curves. Fixation using such rods often involves implantation of rods and attaching them to the spine by hooks and/or screws. Usually, a pair of rods are placed on opposite sides of the portion of the spine to be fixed. 25
Various systems have been developed for cross linking spinal rods to prevent rod migration and to increase stiffness of the paired rod assembly.
Many assemblies used for interconnecting spinal rods, 30 commonly referred to as transverse connector assemblies or rod to rod couplers, utilize a plate mechanism having openings therethrough for adjustably retaining hook systems that are bolted in place in the plate. Examples of such systems are in the U.S. Pat. No. 5,334,203 to Wagner, issued 35 Aug. 2, 1994 and U.S. Pat. No. 5,522,816 to Dinello et al., issued Jun. 4, 1996. The U.S. Pat. No. 5,498,263 to Dinello et al., issued Mar. 12, 1996 discloses a transverse connector system utilizing set screws to interconnect vertebrae coupling members while also using plate members as described 40 above for interconnecting the coupling members such that a squared unit is formed having two sides defined by the plate members and two sides defined by the spaced rod members.
The U.S. Pat. No. 5,312,405 to Korotko et al, issued May 17, 1995 discloses a coupler used for interconnecting spinal 45 rods wherein the coupler itself is a two piece unit, the neck portion of each unit being interconnected by a screw mechanism which clamps a male portion within a female portion of the system. The system also utilizes coupler inserts or yokes which engage a rod and are compressed about the rod 50 when disposed within a seat portion of each coupler and compressed by an instrument which engages the bottom of the rod between the rod and the spine and the top of the coupler.
It would be desirable to provide a coupler which could 55 engage a rod by a simple locking mechanism. It is also desirable to provide a simple interconnecting mechanism between couplers which would require few parts and little manipulation to provide the interconnection. Further, it is desirable to provide a transverse coupler assembly which 60 requires only a simple screw driver or nut driver outside of the assembly for its interconnection between a pair of spinal rods.
SUMMARY OF THE INVENTION
In accordance with the present invention there is provided a coupler for connection to a spinal rod, the coupler includ
ing a transverse connector body including insert seat means for seating a transverse connector insert therein and a transverse connector insert including rod seat means for seating a rod therein. Locking and fixing means draw the transverse connector insert into the insert seat means while simultaneously locking the transverse connector insert in the insert seat means and compressing the rod seat means to lock a rod within the rod seat means.
The present invention further provide a transverse connector comprising a pair of transverse connector bodies including connector means for connecting a rod to each of the transverse connector bodies and interconnecting means for interconnecting the pair of transverse connector bodies along an axis defined by the interconnecting means. The interconnecting means includes length locking means for locking the transverse connector bodies at a predetermined one of a plurality of distances apart along the axis and rotation locking means for preventing relative rotation about the axis between the transverse connector bodies.
BRIEF DESCRIPTION OF THE DRAWINGS
Other advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:
FIG. 1 is a side view, partially in cross section of a transverse connector made in accordance with the present invention;
FIG. 2 is an exploded view, partially in cross section of a coupler made in accordance with the present invention;
FIG. 3 is an exploded view of a second embodiment of the inventive coupler;
FIG. 4 is an exploded view of the transverse connector, partially in cross section;
FIG. 5 is a cross section taken substantially along lines 5—5 of FIG. 4; and
FIG. 6 is an exploded view of the transverse connector in a presassembled position.
DETAILED DESCRIPTION OF THE
A transverse connector constructed in accordance with the present invention is generally shown at 10 in its assembled condition in FIG. 1 and in an exploded view in FIG. 2.
Most generally, the connector 10 includes a pair of connector bodies generally shown at 12,14. Each transverse connector body 12,14 is associated with a connector insert 16,18 for connecting a rod 20,22 to each of the transverse connector bodies 12,14. A locking and fixing mechanism is provided for drawing the transverse connector inserts 16,18 into a seat portion 24,26 and while also simultaneously locking the insert 16,18 in the respective seat portion 24,26 while compressing a rod seat portion 28,30 of each insert 16,18 to lock a rod 20 within the rod seat portion 28,30.
More specifically referring to the transverse connector insert 16, the insert 16 includes a substantially U-shaped portion defined by side walls 32,34 and a base wall 36 combining to form a substantially arcuate inner surface thereof. The arcuate inner surface defines a rod seat surface for retaining a rod 20 therein. The arms 32,34 each have an outer surface 36,38, as best shown in FIG. 2, which taper or flare outwardly from a central axis 40 defined by the length of the insert member 16 when the insert member 16 is not disposed within the seat 24 of the coupler 12. A groove 42