A device for the extraction of screwthreaded sires for osteosynthesis, characterized in that it comprises: at least two lever pieces (20, 21) hinged together and having at one longitudinal end (20a, 21a) seats (22, 23) for grasping the end of a wire (19) which it is required to extract, and clamp means acting on the ohter end of said lever pieces (20, 21) to promote their opening in such a way as to generate a couple of gripping forces on the end of the wire (19). Said clamp means are of screw type and preferably consist of a threaded pin (24) fitted with a knob (24a) and screwed into a tapped piece (25) integral with the end (21b) of one of said lever pieces (21). The end (24b) of the threaded pin nearest the pivot is of a generally frustoconical shape to interact with an inclined plane surface (26) formed in the end (20b) of the other lever piece (20) in such a way as to force it outwards when said pin (24) is screwed in. The thread on said pin (24) and on the tapped piece (25) is opposite to that of the thread of the wires (19).
A Kirschner wire 10 for use in endoscopic surgery is provided, as well as methods and apparatus for installing and removing Kirschner wire 10. Kirschner wire 10 has a holding device 20 for ease of insertion and removal. Kirschner wire 10 is sufficiently short so as not to protrude from the working channel of the endoscope. Insertion instrument 30 has a receptacle 40 which for engagement with holding device 20 of Kirschner wire 10. A targeting ring 46 on insertion instrument 30 enables placement of Kirschner wire 10 under x-ray supervision. Removal device 60 has a wire body 62 with a receptacle 64 located at a distal end thereof for engagement with holding device 20 of Kirschner wire 10. Kirschner wire 10 may be adapted for use in marking a point of entry for a cannulated bone screw or as a point of orientation for an endoscopic procedure.
The method of making a tool for removal of broken screws from a base material, including the material of the bone of a medical patient. One end of the tool has an open bore with interior, left-hand tapered screw threads formed thereon by compressing the tool to form the taper after the threads are formed and presented in a cylindrical shape. The other end of the tool is solid for accommodating a driving tool which rotates the tool in the removal of the broken screw.
A surgical instrument is provided for urging a longitudinal spinal member into a bone fastener. The surgical instrument may include a holder assembly for engaging a bone fastener, the holder assembly preferably comprising a pair of pivotably connected members arranged in a scissor type configuration, and a reducing mechanism for moving the spinal rod with respect to the bone fastener, the reducing mechanism including a rod contacting member and an outer support structure having an opening for receiving at least a portion of the holder assembly and a cavity for receiving at least a portion of the vertical drive mechanism which is sized and configured to threadably engage the holder assembly. The holder assembly preferably includes a pair of jaws each having an extension formed thereon for engaging a recess formed on the lateral side walls of the bone fastener so that the holder assembly can engage the bone fastener without extending into the U-shaped channel. More preferably, the jaws may be sized and configured to engage only one of the side walls formed on the head of the bone fastener. The surgical instrument may further include a horizontal drive mechanism for aligning a laterally offset spinal rod with respect to the bone fastener.
A surgical instrument is provided for urging a longitudinal spinal member into a top-loading spinal implant. The instrument may comprise a holder assembly having a pair of fingers sized and configured to engage the underside of an edge of the spinal implant, a release assembly, and an actuating member. The release assembly may comprise a tubular member and a pusher member, the tubular member being sized and configured to be slidably disposed within the holder assembly, and the pusher member being sized and configured to slidably surround at least a portion of the holder assembly. Upon movement of the actuating member, the holder assembly and the release assembly are moveable with respect to one another so that the longitudinal spinal rod, which is engaged to the pusher member, is urged into engagement with the rod-receiving channel of the spinal implant.
The disclosed cranial flap clamp includes first and second clamping members and an extension member. A portion of the first member is positionable against inferior surfaces of a bone flap and skull and a portion of the second member is positionable against superior surfaces of the flap and skull. The extension member extends from the first member and fits between the flap and skull. The second member has a through opening for receiving the extension member. Movement of either of the clamping members urges the inner surface of the first member against the inferior surfaces of the flap and skull and urges the inner surface of the second member against the superior surfaces of the flap and skull. A stop provided by mechanical deformation of the extension member at any location along its length secures the clamp.
