Abstract: A dynamic cervical plate has a ratchet and pawl mechanism that allows the cervical plate to post operatively shorten the length of the plate and maintain compression between adjacent vertebrae. The plate has an elongated shaft with teeth on one surface and a groove along each longitudinal edge. A lateral plate is attached on one end of the shaft. The plate has screw holes for connecting with the head of a spinal screw. Another lateral plate is slidably engaged in the longitudinal grooves along the shaft and has a spring clip acting as a pawl with the teeth on the shaft. The sliding bar has screw holes on each side of the shaft. The clip is configured to span the screw holes to automatically engage and prevent screws from backing out of the holes.

Abstract: A spinal fusion implant for implantation between adjacent vertebrae is formed in the approximate shape of a hollow cube. The device has an upper section and a lower section separated by a distractor all of which are relatively movable. The sidewalls of the upper section and the lower section terminate in inclined planes so that the sections move away from each other as the wedge shaped distractor increases the height of the device.

Abstract: A drive system for a surgical fastener is composed of a drive tool with a drive tip that mates closely with the recess formed in the head of a threaded fastener. The surgical fastener has a head with a quadrilobe fitting therein which closely mates with the quardilobe tip of the tool. The cooperating drive surfaces align the fastener and tool coaxially and produce four point contact equidistant about the circumference of said fastener significantly reducing angular excursions of the fastener during placement in the bone.

Abstract: A bone plate for stabilizing adjacent vertebrae or ends of a bone has a span for extending across the discontinuity. The span has brackets for attaching to the bone. The brackets have countersunk bores terminating in apertures through which bone screws are placed in the bone. A lock screw aperture is located adjacent the countersunk bores with a portion of the sidewall forming a thin flexible tab in each bore. To prevent back-out of the bone screws, a lock screw is threaded into the lock screw aperture distorting the bore of the bone screw aperture.

Abstract: A polyaxial screw is used to secure orthopedic appliances to bone, particularly the spine. The polyaxial screw has a shaft including a helical screw thread for securing the screw to bone. One end of the shaft has a reverse tapered head tapering toward and away from the shaft from an enlarged median. A spherical shaped swivel, having an opening smaller than the median, is snapped over the head to rotatably engage the shaft. A connector with a dome shaped cavity on one end and bifurcated tabs on the other is connected with the swivel and tightened in place with a set screw and guide ring. An appliance is held between the bifurcated tabs. The tabs are frangible to reduce the profile above the appliance.

Abstract: A cross link system provides stability to spinal rods by maintaining a set distance between the rods. The cross link has a bar with connectors on each end formed with grooves that engage each of the spinal rods. Each of the connectors has a cam that can be manipulated to obstruct the groove and provide a friction fit between the spinal rod and the cross link. The cams have locking nuts that prevent disengagement of the cam and rod. The bar has two shafts interconnected by a bifurcated pin with upstanding ends. a piston is located between the upstanding ends and diverts shear forces along the longitudinal axis of the bar.

Abstract: A dynamic cervical plate has a ratchet and pawl mechanism that allows the cervical plate to post operatively shorten the length of the plate and maintain compression between adjacent vertebrae. The plate has an elongated shaft with teeth on one surface and a groove along each longitudinal edge. A lateral bar is attached on one end of the shaft. The bar has screw holes for connecting with the head of a spinal screw. Another lateral bar is slidably engaged in the longitudinal grooves along the shaft and has a spring clip acting as a pawl with the teeth on the shaft. The sliding bar has screw holes on each side of the shaft. The clip is configured to span the screw holes to prevent screws from backing out of the holes.

Abstract: A bone plate for use in anterior cervical spinal fixation has interlocking components to prevent dislodgement of the plate due to anatomical forces. The plate is formed in the shape of a block letter C and the exposed surface is smooth to prevent trauma to internal body tissue. The plate spans the intervertebral space with each end attached to an adjacent vertebrae by bone screws threadably engaged with the bone. The distal ends of the bone screws The plate has a screw lock in each end for preventing the locking screws from backing out.

Abstract: A spinal fusion device for implantation between adjacent vertebrae is formed in the approximate shape of a hollow cube. The device has an upper section and a lower section relatively movable with regard to each other. The sidewalls of the upper section and the lower section terminate in complementary inclined planes so that as the sections move away from each other the height of the device lessens and as the sections move toward each other the height of the device increases. A distractor is placed within the hollow body and contacts the upper and lower sections by a link which is used to adjust the height of the device.

Abstract: A surgical cable system for fixing bones in a spatial relationship is composed of a multistrand cable having improved flexibility with a fastener on one end and a free end. The fastener has an aperture through which the free end of the cable is inserted after being looped around the bones. The fastener has a stop in the aperture to crimp the cable to permanently fix the loop in the desired position. The tension on the cable is set using a provisional fastener and a tensioner instrument. The provisional fastener serves to separate the permanent fastener from the tensioner and align the cable to reduce friction and slack for more precise control of the tension and the size of the loop. The tensioner has a fixed length shaft providing small precise adjustments in the cable.