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If you live outside the U.S., Flexuspine's FSU may be in a clinical investigation in your country; please contact us if you are interested in more information.  

Caution: Investigational device, limited by Federal (or United States) law to investigational use. The FSU device is currently not available in the United States. Information is presented on the website for general education.  


Flexuspine's FSU (Functional Spinal Unit) Total Spinal Segment Replacement  was designed to provide an alternative to fusion by reestablishing mobility to an affected segment of the lumbar spine. It is a comprehensive device composed of an interbody disc component (Core) and posterior dynamic resistance component (Dampener) that was designed as a system to replace the natural kinematics of the motion segment.


Comprehensive = Interbody Core  +  Posterior Dampener



Core Design Rationale

The unique Cobalt Chrome (CoCr) metal-on-metal articulating design features two paired halves, which facilitate placement on each side of the dural sac intended to allow ample endplate coverage and natural kinematic motion.


Implanted through a familiar bilateral TLIF approach
Paired disc design intended to provide rotation in all directions
Large endplate coverage area may aid in resisting subsidence

The Core is the foundational support for the FSU device. It features strength in compression while providing shear resistance intended to prevent overloading of the posterior dampening component.

The combination of converging inferior endplate anchors, teeth on the superior surface, and Titanium Plasma Spray (TPS) coating was designed to resist migration and provide short and long-term fixation.


Posterior Dampener Design Rationale

The Posterior Dampener component includes a CoCr alloy pedicle screw and sliding rod assembly with silicone dampeners. The rod and screw assemblies are implanted bilaterally after facet removal. The silicone dampeners are designed to provide resistance to flexion-extension, lateral bending, and axial rotation motions.
Dual silicone dampeners and sliding rod design provide physiological resistance (non-linear and direction-specific stiffness) which allows for some forgiveness in the alignment of the Dampeners to the Core component.