Collet

Abstract: A multi-axial bone screw assembly (10) includes a bone screw (11) having a partially spherical head (22). The bone screw head (22) is truncated at an upper surface (24) in which a tool receiving recess (25) is defined. The assembly includes a receiver member (12) including a central bore (34) that defines a tapered recess (35) to receive a contracting collet (13) carrying the head (22) of the bone screw (11). The bore (34) of the receiver member also defines a channel (33) communicating with the recess and configured to receive a spinal rod (R) therein. A portion (37) of the channel is threaded to receive a set screw (14) above the rod. The assembly (10) also includes a contracting collet (13) disposed between the rod (R) and the head (22) of the bone screw (11). The collet (13) defines a partially spherical recess (45) to receive the head (22) of the bone screw, and includes deflectable fingers (50) that substantially surround the screw head. As the set screw (14) is tightened into the receiver member (12), the set screw (14) compresses the rod (R) against the collet (13), which presses the collet (13) into the tapered recess (35) of the receiver member (12), thereby deflecting the fingers (50) of the collet against the bone screw head.

Abstract: A powered surgical apparatus (10) for use with a source of irrigation fluid and a source of suction and for powering a surgical tool (20) such as a cutting blade. The surgical apparatus (10) Includes a handpiece (30) and a cutting blade retention assembly (40) integrated in the (33): distal end of a passage (310) of the handpiece (30). The retention assembly (40) includes an. aligned, pair of radially movable buttons (410), aligned in axiatiy extending passages (35) in communication with the distal end (33) of the passage (310) of the handpiece (30),. the movable buttons (410) can engage with and cause rotational movement of a collet member (430) assembly (60) rotatably supported in the passage (310) In the distal end (33) of the handpiece (33), The collet assembly (50) includes a plurality of rolling lock members 436 which can he moved by the collet member (430) from a first or lock position, in which the lock members (436) are forced by the wall of the passage (310) to extend inwardly of the collet member (430) to engage a groove of the surgical tool (20), and a second or unlocked position, in which the lock members (460) are aligned with a recess (38) in the wall of the passage (310) and are not forced to extend inwardly of the collet member (430).

Abstract: A pedicle screw is provided that includes an upwardly extending collet. The collet may include downwardly extending slots that define deflectable segments therebetween. When a spherical element or other structure, e.g., a non-dynamic stabilizing element, is positioned around the collet, introduction of a set screw causes outward deflection of the upstanding segments into engagement with the spherical element. A snap ring may be interposed between the collet and the spherical element to facilitate positioning therebetween. In an alternative embodiment, a non-slotted collet is employed. In such embodiment, the collet and the spherical element may be threadingly engaged and may include a snap ring therebetween. The pedicle screw subassemblies may be incorporated into a spinal stabilization system which may include a dynamic stabilizing member to provide clinically efficacious results.

Abstract: A polyaxial drill guide includes a body, a collet and a stem. The collet includes a collet shaft having distal and proximal ends and a longitudinal bore. The body includes a conical bore having narrow and wide ends. The distal end of the collet shaft rotatably mounts within the narrow end of the conical bore, with the collet shaft extending toward the wide end of the conical bore, such that the collet shaft (and consequently the longitudinal bore) can be angled within the conical bore at a plurality of angles. The stem includes a shaft having distal and proximal ends and a longitudinal bore. The distal end of the stem shaft mounts to the proximal end of the collet shaft such that the longitudinal bores are co-linear and a drill bit can be inserted into and rotated within the longitudinal bores during a drilling procedure.