Abstract: An external fixation apparatus for applying force against a single isolated plane of deformity in the distal radius for fracture treatment, and which can be used to avoid the need for a bone graft to correct a distal radius malunion. A pair of laterally spaced-apart circular rings are coupled by three rods extending between the rings. Z-shaped brackets are used to offset each of the rods distal to the distal ring, and each rod is pivotally coupled to a Z-shaped bracket by a ball joint. One of the rods is also coupled to a gear mechanism and functions as a pushrod that provides for adjustment of the spacing between the rings along the axis of the pushrod. Each ring carries a radius fixation mechanism, and an optional metacarpal fixation mechanism can be attached to the distal side of the distal ring. An optional ulnar fixation mechanism can also be attached to the proximal ring.

Abstract: A method and surgical instrument is provided for the in situ clamping engagement and reaming of the human patella bone in preparation for the installation of a patellar button prosthesis, the clamp including a rectangular frame wherein a pair of handles are mounted for parallel movement whereby to move their respective jaws into clamped engagement with the opposite faces of the patella, and a guide head defining a fixed stop; and a reaming device including a reamer shaft disposed for rotation relative to the guide head, a depth adjustment head connected to the shaft and adapted to abut the fixed stop, and a reamer blade mounted to the shaft. The shaft is provided with indicia to indicate the thickness of the patella that will remain after the resection.

Abstract: A multi-axial bone engaging fastener assembly includes a bone screw having a partially spherical head. The bone screw head is truncated at an upper surface in which a tool receiving recess is defined. The assembly includes a receiver member including a central bore that defines a tapered recess to receive the head of the bone screw. The bore of the receiver member also defines a channel communicating with the recess and configured to receive a spinal rod therein. A portion of the channel is threaded to receive a set screw above the rod. The assembly also includes a crown member disposed between the rod and the head of the bone screw. As the set screw is tightened into the receiver member, the set screw compresses the rod against the crown member, which presses the head of the bone screw into the tapered recess. In one embodiment, the head of the bone screw includes a flared edge that penetrates at least the crown member as the assembly is tightened.

Abstract: A method and apparatus are provided for replacing the articular surface of the ball of a ball and socket joint. The method comprises the steps of establishing the location of the intramedullary canal adjacent the ball of the joint, and placing a locating component, such as a reamer or broach, in the canal. The method further comprises sizing the articular surface of the ball to be replaced, placing on the component a resecting guide having an opening therein for receiving the component and a complementary surface to the articular surface of the ball to be replaced, rotating the component in a manner determined by the opening in the resecting guide, and resecting the ball in a manner determined by the orientation of the resecting guide.

Abstract: A compression locking variable length cross-link device having a pair of rod hooking elements, each having coupling ends which are attachable to a rod. The opposing ends of the first of these elements includes a pair of extending members each having a hole; the holes being mutually co-linear. The opposing element of the second element includes a single extending member which has an elongated hole, such that when it is disposed between the pair of extending members of the first element, a linear passage is defined through the three holes. A hinge post is disposed in the co-linear passage; the post having a threaded top portion. The elongated hole permits the first and second elements to be translated relative to one another with the hinge post in place. A nut is engageable with the threaded top of the post, such that if tightened, the pair of extending members deflect inwardly into contact with the single extending member of the second element to crush lock the elements together.

Abstract: A guide apparatus of an intervertebral implant which is adapted to firmly fix an implant between adjacent corpus vertebrae includes a grip portion. A hollow inner tube is connected to the grip portion, in which an implant insertion tool can be removably inserted. A first guide projection is provided at the front end of the inner tube to protrude forward therefrom. A movable outer tube is rotatably fitted onto the inner tube. A second guide projection is provided at the front end of the movable outer tube to protrude forward therefrom.

Abstract: A tool for cutting surfaces at repeatable angles relative to the surface being cut is provided. In one embodiment, the tool is used for cutting a bone in a direction perpendicular to a surface of the bone. The tool includes a cylindrical bone cutter having an operable portion located at a proximal end of the cutter for cutting bone. The bone cutter has an internal surface and the internal surface defines an internal bore extending along a longitudinal axis of the cutter from a proximal end to a distal end. A probe, slidably mounted within the bore of the cutter, extends beyond the operable portion of the cutter, and is biased towards the bone surface. An indicator coupled to the probe designates the position of the probe relative to the operable portion of the cutter.

Abstract: In a puller for correcting an upper jaw (19) on a skull (20), for eliminating an overbite, crossbite, or cleft palate for example, a basic body (11) is provided with elements (4, 18, 22) for attachment to upper jaw (19) and is movable in correction direction (x.sub.1).

Abstract: Fasteners having coordinated self-seeking conforming members or implanting into a cavity such as a hole, tube, or hard tissue defect are provided. An actuator mechanism translates applied force to conform members of a plurality of members to the cavity. The fasteners may be used for implanting a prosthetic device into hard tissue of humans or animals, for anchoring a device while the device is being worked on, for centering a device in a hole or tube, such as in well technology. The mechanism operates expanding members so that they independently or dependently conform and apply controlled and known pressure to surrounding materials.

Abstract: A polyaxial orthopedic device for use with rod implant apparatus includes a screw having a curvate head, a two-piece interlocking coupling element which mounts about the curvate head, and a rod receiving cylindrical body member having a tapered socket into which both the screw and the interlocking coupling element are securely nested. The interlocking coupling element includes a socket portion which is slotted and tapered so that when it is radially compressed by being driven downwardly into the tapered socket in the cylindrical body it crush locks to the screw. The securing of the rod in the body member provides the necessary downward force onto the socket portion through a contact force on the top of the cap portion. Prior to the rod being inserted, therefore, the screw head remains polyaxially free with respect to the coupling element and the body.

Abstract: The device comprises at least one vertebral rod (2), pedicle screws (3), and connectors (1) interconnecting the rod and the screws. The connectors (1, 10) define an oblong opening (5) extending transversely of the rod and passed through by the screw. The intermediate connectors (1) are made of a malleable plastically deformable material having a capacity of elongation of at least about 20%. The intermediate anchorages of the instrumentation are provided with such connectors (1) which are plastically deformable in their branches (4) passed through by the screw by the effect of the tightening of nuts (8) on the screws when placing the device in position and undeformable by the effect of the bending moments transmitted by the spine in vivo at values lower than 4.5 N.m. The chosen material may be for example pure titanium and its plasticity enables the surgeons to easily adapt the connectors to the differences of alignment, angulation and depth of penetration of the pedicle screws.

Abstract: An osteosynthetic alignment or fixation device has a flexible mode making it more easily positioned and a rigid mode in which it provides a desired measure of support in a desired shape to a fractured or deformed bone.

Abstract: A device for use in transplantation of bone tissue material (3) in a cavity (2) in bone comprises a surface (1) for compacting the bone tissue material in the cavity. The compacting surface has a relief like structure on its compacting surface (4) for contact with the bone tissue material.

Abstract: The drill bit for drilling a hole in bone structure is made to inherently prevent cutting when the resistive force is removed by providing an annular wall with a cutting edge formed on the bottom edge and lying in a plane that is in the circumferential plane of the annular wall and providing a shield in the same plane and disposed adjacent to the cutting edge that is automatically displaced when a resistive load is applied and automatically returns to shield the cutting edge when the resistive load ceases. In one embodiment the wall of the annular wall is judiciously slotted to provide the automatic movement of the shield and in another embodiment the shield is spring load to be displaced and returned to its original position. The perforator of this invention includes safety mechanism that prevents penetration of the perforator when the drill bit has completed the cutting operation and the resistive load is removed.

Abstract: The present invention is a polyaxial locking screw plate assembly for immobilization of vertebral bones, via fixation to surfaces thereof. The assembly includes a plate, having an upper portion and a lower portion, each of which has a pair of tapered holes, into which holes coupling elements and bone screws may be inserted. The upper part of the holes further includes an annularly recessed channel in which a snap-ring is disposed. The coupling elements each have an axial taper which matches the taper of the holes, and an interior semi-spherical concave surface in which the semi-spherical head of a bone screw may be polyaxially mounted. The bone screws are inserted through the holes until the coupling element engages and expands the snap-ring.

Abstract: An anchoring member is provided with a shaft 2 for fastening to a bone and a head 3 for connection with a rod 10, the head being connected to the shaft and having a generally U-shaped cross-section with a base and two legs laterally defining a first channel for receiving the rod. The rod is retained in a desired position within the channel by a fastening member. In order to allow the anchoring member to be used not only with a rod of the appropriate diameter, but also with rods having smaller diameters the anchoring member comprises an insert member 13, 13' having a generally U-shaped cross-section forming a second channel 18 defined by its two free sides 14, 15 for receiving a rod 17 having a smaller diameter. The outer curvature of the U-shaped cross-section of the insert member 13, 13' is substantially equal to or slightly smaller than the internal curvature of the first channel 4.

Abstract: An internal fixation device used in surgical procedures to the internal fixation of femoral hip fractures, especially prevalent in elderly persons suffering from osteoporosis. This device includes a femoral shaft side plate, an internally threaded sleeve pivotally mounted on said side plate, an elongated screw member insertable in the sleeve to fasten the sleeve in the femoral head, and wedge-shaped washer means for fixing the pivot angle between the sleeve and the femoral side plate at the natural angle between the axis of the femoral neck the femoral shaft of the hip being treated.

Abstract: An apparatus and method for tightening and crimping a surgical wire used for orthopedic purposes. The apparatus of this invention includes a pair of operating handles which are biased apart and which operate a pair of opposed jaws to which they are connected. Disposed on opposite sides of the operating handles are a pair of capstans. The jaws are adapted to hold a crimp member therein without deforming it while opposite ends of a length of wire are passed through the crimping member in opposite directions. Each end of the wire is wrapped about an associated capstan. A ratchet handle simultaneously rotates both capstans to wrap the opposite ends of the wire. Once the desired traction force has been achieved, the jaws are further activated to crimp the crimp member. A ring-shaped crimp member is also disclosed which has a central opening extending along the axis thereof and two parallel channels, one channel being disposed on either side of the central opening.

Abstract: An orthopedic pin insertion tool is provided which can be used as a hand-driven pin insertion tool or a power-driven pin insertion tool. The tool comprises a chuck and a chuck extension with a central passage which can be either stopped or continuous.

Abstract: A bone fixation device such as a screw, pin, staple, cable or anchor has a microtextured contact surface to enhance installation or gripping characteristics, preferably by providing directional or anisotropic engagement. A surface texture comprised of patterned microfeatures imparts a roughness or actual mechanical engagement that prevents loosening. In different embodiments the features resemble an array of microbumps or pyramids, or anisotropic features such as rasp teeth, shingles, or slanted cantilevered fiber/rods. The use of microbumps present a smaller surface area when moving, while providing full area contact after the surfaces have relaxed or decompressed; installation may be effected with low force, while high static or resting friction prevents disengagement.