摘要:
A compression locking variable length cross-link device having modular components, including rod and/or pedicle screw coupling elements each having a hole which may be disposed co-linearly with respect to other such holes in opposing elements such that a threaded hinge-post may be inserted therein. A nut is utilized to compress the elements together to rigidly secure the elements once they have been properly positioned relative to one another. In an additional set of embodiments, a linkage member having an elongate hole therein may be used to couple similar elements thereto in a similar flexible hinge-post manner such that the elements may be coupled to the linkage member instead of to the opposing elements directly.
摘要:
A modular polyaxial pedicle screw and orthopaedic rod implant device including same includes a shaft portion, a cuff, a stem portion, and a rod coupling sub-assembly. The shaft portion is designed to be inserted into the pedicle, has a recess formed in its top, and includes a threading formed on the exterior surface around the recess. The stem portion is a threaded post having an enlarged ball formed at the base thereof, the ball being ideally suited to polyaxially rotate within the recess of the shaft. The cuff is a cylindrical element designed to seat around the interface of the ball portion of the stem and the recess of the shaft, initially so that the stem and shaft may polyaxially rotate relative to one another, and subsequently to hold the stem and shaft in final securement. The rod coupling sub-assembly consists of a rod coupling element which is mountable on the post portion of the stem, and a top locking nut which secures the rod coupling element to the post between the nut and the cuff. Spacer elements may be utilized which are positioned on the post between the cuff and the rod coupling element to permit axial variability on the stem in addition to the angular variability inherent in the shaft and stem interface.
摘要:
A polyaxial locking cervical screw and plate assembly for immobilization of cervical bones, via fixation to surfaces thereof, including a plate, having a pair of elongated tapered holes in the top and bottom thereof, into which holes elongated coupling elements and screws may be inserted. Each coupling element has an equivalent taper which matches the taper of the holes in the plate, and an interior semi-spherical curvate surface in which the curvate head of the screw may be polyaxially mounted. The coupling elements are initially disposed in the holes in the plate such that they may slide axially therein. The bone screws are inserted through the respective coupling elements until the heads thereof enter the curvate volumes thereof. Once the head is fully seated in the coupling element, advancement of the screw causes the coupling element to crush lock to the plate and to the head of the screw.
摘要:
A polyaxial orthopedic device for use with rod implant apparatus which includes a screw having a head, a tubular body having holes in the top, side and bottom therof, and a rod coupling element. The head of the screw is disposed in the body with the shaft of the screw extending out the bottom hole, such that the body and the screw may initially rotate relative to one another. The rod coupling element has a ball shaped end which seats in the body with the remainder of the rod coupling element extending out of the side hole of the body, such that the rod coupling element and the body are initially polyaxially coupled relative to one another. The ball end of the rod coupling element is disposed on top of the head of the screw. A set screw is provided in the top of the body, the tightening of which causes the ball, head, and body to be crush locked together, thereby preventing further relative motion.
摘要:
A cross-linking member for rigidly coupling interbody fusion devices such that they have reduced tendencies to dislocate subsequent to implantation as well as an interbody fusion assembly which includes at least two interbody fusion devices rigidly coupled together by a cross-linking member.
摘要:
The present invention is a selectively expandable bone fixation screw-sleeve device which provides substantially greater holding strength in human bone than other bone screw devices. The sleeve element of this invention includes several embodiments, each having at least one corresponding screw element for selectively expanding a portion of the sleeve once it has been inserted into the bone. More specifically, in several embodiments, the sleeve includes a series of vertical slots in the end, or ends, of the cylindrical body of the sleeve. The slots define, therebetween, sections which are contiguous with the remainder of the cylindrical body, and which may rotate radially outward. In these embodiments, the sections are designed having a varying thickness, for example a single or double wedge profile, such that the insertion of the screw element into the sleeve deforms the shape of the sleeve by causing the sections to flair outward. In a different embodiment, the slots, and sections, are designed into the axially intermediate central portion of the cylindrical sleeve, and therefore flair outwardly therefrom upon insertion of a screw within the sleeve. As this invention is intended to provide imporved fixation support for orthopedic implantation assemblies, each embodiment may further include means coupled or integral with the sleeve or screw for coupling an orthopedic implant to it.
摘要:
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. In a preferred embodiment, the cap portion and the socket portion are formed and coupled in such a way that when the cap portion is compressed toward the socket portion, there is an additional inward radial force applied by the cap portion to the socket portion, thereby enhancing the total locking force onto the head of the screw.
摘要:
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. Once the coupling element is fully seated in the hole, thereby locking the screw in place and the coupling element in the hole, the snap-ring contracts to its undeflected position and prevents the coupling element and screw from backing out of the hole in the event of loosening.
摘要:
A polyaxial orthopedic device for use with rod implant apparatus includes a screw having a head, a tubular body having holes in the top, side and bottom thereof, and a rod coupling element. The head of the screw is disposed in the body with the shaft of the screw extending out the bottom hole, such that the body and the screw may initially rotate relative to one another. The rod coupling element has a ball shaped end which seats in the body with the remainder of the rod coupling element extending out of the side hole of the body, such that the rod coupling element and the body are initially polyaxially coupled relative to one another. The ball end of the rod coupling element is disposed on top of the head of the screw. A set screw is provided in the top of the body, the tightening of which causes the ball, head, and body to be crush locked together, thereby preventing further relative motion.
摘要:
A hook device for use with support rod implantation apparatus, having a rod receiving body polyaxially mounted to a blade portion such that the body may be polyaxially manuevered relative to the blade, for easy rod coupling. The blade portion has a semi-spherical head portion which sits above the lamina. The rod receiving portion is a separate coupling element having lower and upper portions. The lower portion is slotted and tapered, and has a semi-spherical interior chamber in which the semi-spherical head is initially polyaxially disposed. The upper portion has a pair of upwardly extending members, defining therebetween a channel for receiving the rod. The uppermost parts of the upwardly extending members include an threading for receiving a top locking nut. A locking ring is disposed about the coupling element, substantially below the side recess; the top of the coupling element being initially positioned above the lower ledge of the side recess such that the rod, when initially disposed therein, seats against the top surface of the locking ring. When the rod is in place, the top locking nut is tightened to provides a downward force onto the rod. The rod, in turn, applies a force against the locking ring to descend down the tapered lower portion, therein locking the semi-spherical head in the interior chamber of the coupling element, and locking it into position relative to the blade portion. In an alternative variation, a rod retaining sleeve may be provided between the locking ring and the nut.