Abstract: A facet joint replacement system includes an inferior implant with an inferior articular surface, a superior implant with a superior articular surface, and an optional crossbar. The inferior implant and the superior implant are each polyaxially adjustably connected to fixation elements which anchor the implants to adjacent vertebrae. The optional crossbar may be polyaxially adjustably connected to bilateral implants. The system components may be provided in kits which provide components of various sizes and shapes. A set of surgical instruments may facilitate implantation of the facet joint replacement system by providing tools for bone preparation, trialing, implant insertion, implant alignment, and lock-out of modular interconnections.

Abstract: A system for replacing at least a portion of a natural facet joint includes a fixation member implantable in a vertebra, an inferior facet articular surface and an inferior strut which may be formed separately from the inferior articular surface. The inferior strut has a first end securable to the fixation member and a second end which may comprise a sphere with a hemispherical surface. An attachment mechanism may include a capture feature shaped to receive the second end of the inferior strut, and the mechanism may provide an adjustable configuration, allowing polyaxial adjustment between the inferior articular surface and the second end. A locking member may be actuated to exert force on the second end to provide a locked configuration. The system may further include a superior facet joint implant with a superior articular surface shaped to articulate with the inferior articular surface.

Abstract: A system includes an implant with an articulation surface, a fixation member which may be anchored in a bone, and a base portion which may receive the fixation member. The base member may comprise a bone-engaging portion and an attachment portion. The base member may receive the fixation member such that a threaded portion of the fixation member and the bone-engaging portion of the base member may be seated in the bone. The implant may be attached to the attachment portion of the base member. The base member may be configured in a variety of shapes and may include fins, teeth, pegs or other anti-rotation features, and may include a bone ingrowth surface. The attachment portion may be tapered and attachable to the implant through a taper-lock.

Abstract: A facet joint replacement system includes an inferior implant with an inferior articular surface, and a superior implant with a superior articular surface. The implants may be coupled together by a detachable coupler which can align and rigidly hold the inferior and superior articular surfaces in a preferred alignment relative to one another. A portion of the coupler may be deformable to allow detachment of the coupler from at least one of the implants. In one method of implantation, the superior and inferior implants may be aligned and coupled together with the coupler, and then secured to fixation members anchored in adjacent vertebrae. Alternatively, a first implant may be secured to a fixation member anchored in a first vertebra, and a second implant coupled to the coupler, aligned with the first implant and then secured to a fixation member anchored in a second vertebra. A tool may grip, position and/or deliver the coupler and the implants.

Abstract: A system for replacing at least a portion of a natural facet joint includes a fixation member implantable in a vertebra, an inferior facet articular surface and an inferior strut which may be formed separately from the inferior articular surface. The inferior strut has a first end securable to the fixation member and a second end which may comprise a sphere with a hemispherical surface. An attachment mechanism may include a capture feature shaped to receive the second end of the inferior strut, and the mechanism may provide an adjustable configuration, allowing polyaxial adjustment between the inferior articular surface and the second end. A locking member may be actuated to exert force on the second end to provide a locked configuration. The system may further include a superior facet joint implant with a superior articular surface shaped to articulate with the inferior articular surface.

Abstract: A facet joint replacement system includes an inferior implant with an inferior articular surface, and a superior implant with a superior articular surface. The inferior implant may comprise an inferior strut, and a polyaxially adjustable, lockable mechanism which couples the inferior articular surface with a first end of the inferior strut. A second end of the inferior strut may be secured to a polyaxially adjustable, lockable fixation assembly securable in a vertebra. The first end of the inferior strut may be post-shaped, and the second end ring-shaped, and vice versa. The superior implant may be secured to a polyaxially adjustable lockable fixation assembly securable in a vertebra. Inferior and superior implants may be implanted individually, paired on one lateral vertebral side, bi-laterally, and/or in multiple vertebral levels. A crosslink may be secured to one implant and extend across a vertebral sagittal plane to a second implant. A clip may align the articular surfaces during implantation.

Abstract: A facet joint replacement system includes an inferior implant with an inferior articular surface, and a superior implant with a superior articular surface. The inferior implant may comprise an inferior strut, and a polyaxially adjustable, lockable mechanism which couples the inferior articular surface with a first end of the inferior strut. A second end of the inferior strut may be secured to a polyaxially adjustable, lockable fixation assembly securable in a vertebra. The first end of the inferior strut may be post-shaped, and the second end ring-shaped, and vice versa. The superior implant may be secured to a polyaxially adjustable lockable fixation assembly securable in a vertebra. Inferior and superior implants may be implanted individually, paired on one lateral vertebral side, bi-laterally, and/or in multiple vertebral levels. A crosslink may be secured to one implant and extend across a vertebral sagittal plane to a second implant. A clip may align the articular surfaces during implantation.

Abstract: A fixation system is designed to lock an elongated member within a housing member, permitting positional and/or orientational adjustment of the elongated member prior to locking. The system includes a housing member, a slotted spherical collet, an elongated member, and may include a tapered wedge, which may be a discrete component or formed as part of the elongated member. The housing member and/or elongated member may be implantable. The elongated member may be positioned in the wedge, the wedge in the collet, and the collet in the housing such that when compression force is applied to the wedge and the collet, the wedge contracts about the elongated member and the collet expands to engage the housing, thus locking the elongated member relative to the housing. The collet may have a tapered channel with a degree of taper equal to the tapered wedge. The collet may have multiple slots to allow uniform radial expansion and compression.