Abstract: A compliant intervertebral spacer according to the present invention replaces a damage intervertebral disc and functions to maintain disc height and prevent subsidence with a large surface area while substantially reducing patient recovery time. The compliant intervertebral spacer for spanning a space formed by upon removal of an intervertebral disc includes two end plates sized and shaped to fit within an intervertebral space and a compliant connector interconnecting the inner surfaces of the two end plates in a manner which limits motion between the plates to less than a total of 5 degrees of motion in any direction. The intervertebral spacer is configured to permanently maintain the disc space between the two adjacent discs without the use of bridging bone.

Abstract: An artificial intervertebral disc with shock absorption includes upper and lower plates disposed about a shock absorbing movable core. The upper and lower plates have an outer surface which engages a vertebrae and an inner bearing surface. The shock absorbing core includes a unitary member of a rigid material having at least one lateral cut between upper and lower surfaces of the core to allow the upper and lower surfaces to move resiliently toward and away from each other. This allows the core to absorb forces applied to it by the vertebrae.

Abstract: In some embodiments, an implant may include a porous component and a load bearing component at least partially surrounding the porous component. The porous component has a porosity that is greater than the porosity of the load bearing component. One or more protrusions may be present on the load bearing component. The porous component and/or a load bearing component may be at least partially composed of calcium phosphate.

Abstract: Systems and methods are provided for the mixing of materials to form a homogenous mixture and for delivering the mixture to a target site. In one embodiment a vial containing a liquid monomer is detachably engaged with a mixing chamber. The liquid monomer flows into the mixing chamber and combines with a powder to form a flowable composition such as bone cement. The bone cement may then be injected from the device to a target location.

Abstract: Methods and apparatus for performing a medical procedure which involves penetrating a bone structure are disclosed. According to one aspect of the present invention, a method for performing a surgical procedure includes introducing an assembly that includes a threaded cannula and a stylet into a bone structure. The threads have a shape that allows the cannula tip to be pushed into the bone body yet prevent the tip from being pulled out of the bone body. In one embodiment, the threads have a buttress shape. The method may also include applying a rotational motion, as for example a torque, to the threaded cannula to adjust the depth of insertion with respect to the implantation site when it is determined that the depth of insertion is to be adjusted.

Abstract: Methods and systems are provided for the transfer of viscous therapeutic material from one chamber or device to another chamber or device in a fluidly sealed manner, wherein components of the system may be discrete or integrated. The system and methods provide for mixing and dispensing of therapeutic materials such as bone cement.

Abstract: Instruments and methodology for nonlinear access to bone tissue sites are described. Embodiments disclosed include a conduit for delivering material or a medical device to a site and a core member that is able to steer the conduit and allow the combination to be advanced thorough cancellous bone. A cannula and stylet may be provided to first advance through hard bone. The core member includes a curved tip that may be straightened by the cannula or an actuator sheath to vary sweep of the curve. An obturator may be included in the system. This instrument may include a flexible portion as well. Each of the obturator and conduit may be provided with any of a variety of active tips. The systems may be used to perform hard tissue site implantation, for example, in connection with a high pressure injection system.

Abstract: An injection system for delivering viscous fluids is disclosed. Exemplary fluids included flowable hard tissue implant material such as Polymethylmethacrylate (PMMA). The system comprises a manual actuator, a control line and a dispenser. The control line may be flexible cable set within a housing running between the actuator and dispenser head. In which case, the actuator is designed to enable reciprocal movement of the cable relative to the cable housing. The actuator may be designed for one-handed use like a syringe. Components of the dispenser may be utilized as a mixing vessel prior to inserting a drive unit to enable fluid delivery. Prior to use, fluid is loaded into a portion section of the drive unit from a reservoir section of the dispenser head by retracing the cable via the retractor. Fluid is expelled from the dispenser portion of the system upon advancing the cable.