Abstract: A spinal implant system for correcting spinal deformities and abnormalities includes an elongated spinal rod configured to be implanted adjacent the spinal column and spanning across several vertebral levels. A number of fixation elements, such as spinal hooks, are provided for engaging vertebrae at a number of vertebral levels. At least some of the fixation elements includes an elongated stem projecting from a vertebra engaging portion. The stems of each of the fixation elements are connected to the spinal rod by way of a rod connector having a one-piece body defining a rod channel adapted to receive the spinal rod therethrough, a stem bore adapted to receive a stem therethrough, and a threaded bore. The stem bore and rod channel intersect to permit contact between the rod and the stem of a fixation element. The threaded bore intersects either the rod channel or the stem bore so that a set screw threaded into the threaded bore bears against the spinal rod or fixation element stem.

Abstract: A disk arthroplasty device (310) is provided for replacement of a spinal disk. The device is implantable into a resected disk space and is formed with ball (346) and socket (326) members and shaped to provide lateral bending and backward extension of up to about 5.degree. and forward flexion of up to about 15.degree.. Four embodiments (10), (110), (210) and (310) permit up to about 5.degree. axial rotation and a fifth embodiment (410) permits unrestricted axial rotation. Metal insert cups (70) and (170) are provided for attaching to the device surfaces and are convexly shaped along one axis to conform to the natural contours of the top and bottom vertebra surfaces. The metal insert cups (70) and (170) provide tensile support to the structure and provide for the attachment of additional structures for retaining the device in position after implantation into a disk space.

Abstract: Spinal implants with features for anchorage in or onto bone or to connectors, have a body with an upwardly opening channel receiving a spinal rod therein. The channel has sidewalls with a curved slot in each of the sidewalls. A cap is mounted on the implant body and has a central portion received in the channel and has tongues at each side of the central portion, the tongues being received in the curved slots in the sidewalls. A set screw threaded into the cap engages the spinal rod and clamps the rod between the body and the set screw and fixes the cap to the body. The curved slots enable installation of the cap in minimal space measured lengthwise of the rod. Each implant body has an integral bone screw, or bone hook, or lateral connector rod or parallel spinal rod receiving body thereon.

Abstract: A spinal fixation system comprises an elongated fixation plate (13) having an elongated slot (21) with a number of concave depressions (28,25) formed at the top and bottom surfaces (19,17) of the plate. The system further includes a pedicle screw (40) and a nut (32) for load transmission between a vertebra and the plate. The pedicle screw includes a threaded nut engaging portion (42), a threaded bone engaging portion (44) and an intermediate portion (46) therebetween which has rigid upper and lower arcuate surfaces (47) that are complementary to the concave depressions in the plate. The nut also includes a rigid lower arcuate surface (36) which is complementary to the upper concave depressions of the plate. In one assembled configuration the plate is clamped between the upper arcuate surface of the pedicle screw and the nut. In an alternative embodiment of the pedicle screw (70), the intermediate portion has an upper and lower arcuate surface (79,77) of different spherical radii of curvature.

Abstract: A spinal implant system for correcting spinal deformities and abnormalities includes an elongated spinal rod configured to be implanted adjacent the spinal column and spanning across several vertebral levels. A number of fixation elements, such as spinal hooks, are provided for engaging vertebrae at a number of vertebral levels. At least some of the fixation elements includes an elongated stem projecting from a vertebra engaging portion. The stems of each of the fixation elements are connected to the spinal rod by way of a rod connector having a one-piece body defining a rod channel adapted to receive the spinal rod therethrough, a stem bore adapted to receive a stem therethrough, and a threaded bore. The stem bore and rod channel intersect to permit contact between the rod and the stem of a fixation element. The threaded bore intersects either the rod channel or the stem bore so that a set screw threaded into the threaded bore bears against the spinal rod or fixation element stem.

Abstract: A system for achieving reduction of curvature of the lumbar region of the spine associated with spondylolisthesis includes transverse plates affixed to vertebrae L4 and L5 and sacral plates affixed to opposite sides of the sacrum. These plates in combination with the longitudinal plate along the posterior anterior plane in which the spinous processes lie allows for effective reduction of the curvature and secure fixation of this region of the spine. The transverse plates include textured surfaces which allow them to mate in a manner which prevents undesirable slippage therebetween. The system is also compact and does not interfere with the paraspinal muscles which run along either side of the spinous processes.

Abstract: A system for achieving reduction of curvature of the lumbar region of the spine associated with spondylolisthesis includes transverse plates affixed to vertebrae L4 and L5 and sacral plates affixed to opposite sides of the sacrum. These plates in combination with the longitudinal plate along the posterior anterior plane in which the spinous processes lie allows for effective reduction of the curvature and secure fixation of this region of the spine. The transverse plates include textured surfaces which allow them to mate in a manner which prevents undesirable slippage therebetween. The system is also compact and does not interfere with the paraspinal muscles which run along either side of the spinous processes.

Abstract: A spinal implant system for correcting spinal deformities and abnormalities includes an elongated spinal rod configured to be implanted adjacent the spinal column and spanning across several vertebral levels. A number of fixation elements, such as spinal hooks, are provided for engaging vertebrae at a number of vertebral levels. At least some of the fixation elements includes an elongated stem projecting from a vertebra engaging portion. The stems of each of the fixation elements are connected to the spinal rod by way of a rod connector having a one-piece body defining a rod channel adapted to receive the spinal rod therethrough, a stem bore adapted to receive a stem therethrough, and a threaded bore. The stem bore and rod channel intersect to permit contact between the rod and the stem of a fixation element. The threaded bore intersects either the rod channel or the stem bore so that a set screw threaded into the threaded bore bears against the spinal rod or fixation element stem.

Abstract: A method for internal fixation of vertebra of the spine to facilitate graft fusion includes steps for excising the nucleus of an affected disc, preparing a bone graft, instrumenting the vertebrae for fixation, and introducing the bone graft into the resected nuclear space. Disc resection is conducted through two portals through the annulus, with one portal supporting resection instruments and the other supporting a viewing device. The fixation hardware is inserted through small incisions aligned with each pedicle to be instrumented. The hardware includes bone screws, fixation plates, engagement nuts, and linking members. In an important aspect of the method, the fixation plates, engagement nuts and linking members are supported suprafascially but subcutaneously so that the fascia and muscle tissue are not damaged. The bone screw is configured to support the fixation hardware above the fascia.

Abstract: A system for achieving reduction of curvature of the lumbar region of the spine associated with spondylolisthesis includes a hook assembly attached to vertebra L4, transverse plates affixed to vertebrae L4 and L5, and sacral plates affixed to opposite sides of the sacrum. The hooks and the plates in combination with the longitudinal plate along the posterior anterior plane in which the spinous processes lie allows for effective reduction of the curvature and secure fixation of this region of the spine. A related system for stabilizing the cervical region of the spine includes transverse plates affixed to vertebrae C3, C4, and C5. These plates in combination with a longitudinal plate allows for effective stabilization. The transverse plates include textured surfaces that allow them to mate in a manner which prevents undesirable slippage therebetween. The system is also compact and does not interfere with the paraspinal muscles which run along either side of the spinous processes.

Abstract: An attachment plate for use with a spinal rod system converts a normally side-tightening eyebolt to a top-tightenable arrangement for engaging spinal fixation elements to the spinal rod. The plate is configured for use with spinal fixation elements having a posteriorly projecting central post, one lateral surface of the post contacting the spinal rod when the rod extends through an aperture of the eyebolt. The attachment plate is generally L-shaped with a slot in one portion for receiving the posteriorly projecting threaded post of the eyebolt. The plate includes a flange portion having a surface configured to engage the lateral surface of the fixation element post opposite the spinal rod. The attachment plate includes a camming segment to provide a clamping force component directed toward the flange portion of the plate to thereby tightly clamp the spinal rod to the fixation element post when a nut is threaded onto the eyebolt threaded post.

Abstract: A disk arthroplasty device (310) is provided for replacement of a spinal disk. The device is implantable into a resected disk space and is formed with ball (346) and socket (326) members and shaped to provide lateral bending and backward extension of up to about 5.degree. and forward flexion of up to about 15.degree.. Four embodiments (10), (110), (210) and (310) permit up to about 5.degree. axial rotation and a fifth embodiment (410) permits unrestricted axial rotation. Metal insert cups (70) and (170) are provided for attaching to the device surfaces and are convexly shaped along one axis to conform to the natural contours of the top and bottom vertebra surfaces. The metal insert cups (70) and (170) provide tensile support to the structure and provide for the attachment of additional structures for retaining the device in position after implantation into a disk space.

Abstract: A clamp is provided for clamping a spinal rod to a vertebral fixation element which permits access directly from the top of the instrumentation site. The clamp includes a body defining a channel configured to receive the spinal rod and a pair of conical sleeves for restrainably securing the spinal rod to the clamp by forcibly inserting the sleeves between the spinal rod and the channel. The clamp further includes a projection extending from the body, terminating in a T-bar, and a washer slidably disposed on the projection between the T-bar and channel. As the conical sleeves are forcibly inserted into the channel, the sleeves bear upon the the washer and displace the washer in the direction of the T-bar, thereby clamping the vertebral fixation element between the T-bar and washer. The dual function of the conical sleeves thereby clamps the spinal rod to a vertebral fixation element.

Abstract: A drill and tap guide system is disclosed which can be mounted on a bone plate to provide a finn foundation for accurately drilling and tapping screw holes into vertebra to be instrumented. The drill and tap guide system includes an assembly support which is engaged to the plate by way of a positioning screw and cross pins mounting the positioning screw to the guide body. A tap sleeve and drill guide can then be supported by the assembly support, which both thereby provide accurate positioning for a drill. In another embodiment, the system includes a guide apparatus for holding a spinal plate and drilling and tapping the bone. The guide comprises two arms which pivot with respect to each other and a foot attached at the end of each arm. Each foot has a hook which is adapted to securely grasp a spinal plate and a pair of thru-holes. Each hole is aligned with a screw bore in a spinal plate when the guide assembly is engaged to the plate.

Abstract: A double-apertured L-shaped crimp is crimped to one end of a cable. The other end of the cable is passed around the bone or bones and, if the situation requires, any orthopedic appliance or device to be attached to the bones, and it is then passed through the other aperture in the crimp. The cable is then tensioned by application thereto of a tensioning tool with the tool applied to the cable and to an abutment face of the crimp, whereupon the cable is tensioned. Then the cable portion in the aperture adjacent the tensioning tool is crimped onto the cable to complete the attachment. Then the tensioning tool is removed, and the free end of the cable is cut off at the abutment surface.

Abstract: A reciprocating cutting instrument includes an outer tube housing an inner reciprocating cutting blade. The cutting blade is engaged to a source of power, namely a motor, through a transmission and drive mechanism. This transmission and drive mechanism converts rotary drive movement of the motor to reciprocating movement of the cutting blade. A cam is provided that engages the spindle of the motor, the cam formed by a generally cylindrically shaped cam barrel with a cam channel defined in the outer surface of the barrel. A drive ball rides within the channel and is supported within a boss of a linear in-line driver. The in-line driver reciprocates within a bearing housed by a driver cartridge. Pressure between the drive ball and the cam channel is maintained by a set screw threaded into the boss in the in-line driver. As the motor rotates, the spindle, which is engaged to the cam, rotates the cam barrel.

Abstract: A spinal system yields a triangular construct across a vertebral body and a quadrilateral construct between vertebral levels. A first pair of screws are engaged in a vertebra on opposite sides of the spinal midline. A longitudinally splined rod, bent into a V-shape, spans between the pair of screws with its vertex generally at the spinal midline. An eyebolt fastener includes a serrated aperture to receive the transverse splined rod, and a threaded post extending through a yoke in the screws. A nut engages the post to clamp eyebolt, rod and yoke together. A second set of fasteners is provided to engage a pair of rigid plates to the transverse rod, each plate spanning between two vertebral levels on either side of the spinal midline. The other end of each plate is engaged to a similar triangular rod construct in the adjacent vertebra.

Abstract: A device is provided on spinal fixation hook or screw elements along a spinal implant rod for preventing or inhibiting them from unintentional sliding on the rod during handling prior to implantation in vivo. One embodiment uses a set screw in an eyebolt and which engages the rod. Another uses a plastic plug in an eyebolt and which engages the rod. A third uses a grooved aperture in the eyebolt cooperating with a grooved rod to inhibit unintentional sliding of the eyebolt on the rod.

Abstract: An apparatus for minimally invasive tissue removal contemplates a system including a tissue cutting tool having a motor driven cut-ting blade reciprocating within a percutaneously introducable cannula. In accordance with one method of the invention, the frequency of reciprocation of the cutting blade is tuned to a characteristic frequency of the target tissue to be excised, which frequency is a function of certain properties of the target tissue and the surrounding tissue. Cutting at the characteristic frequency of the target tissue not only enhances the speed and efficiency of the tissue excision, but also minimizes the risk of cutting surrounding tissue. Another aspect of the system includes feedback control of both aspiration and irrigation circuits of the system. With the feedback control, coupled with user settable inputs, the surgeon can control the system to "tease" tissue into the cutting opening to provide more manageable bite sizes of the excised tissue.

Abstract: An interbody fusion device includes a pair of lateral spacers and a pair of central spacers, each sized for percutaneous introduction through a disc resection portal in the disc annulus. Each of the lateral spacers includes opposing side faces defining a channel therein, while each of the central spacers includes arms at their opposite ends configured to be received within a channel of a corresponding lateral spacer. The arms and channels are interlocking to prevent separation of the components once assembled within the intradiscal space. The assembly of the central and lateral spacers defines a cavity therebetween for insertion of bone graft material. The central and lateral spacers are configured so that the bone graft cavity is oriented over the weakest, but most vascular and biologically active, bone of the vertebral body, while the lateral spacers are situated adjacent the disc annulus and over the strongest vertebral bone.