LOCK-IN Spinal Fixation System

The LOCK-IN Spinal Fixation System is a posterior spinal fixation device consisting of polyaxial pedicle screws (expandable and non-expandable), titanium rods, rod lockers, and crosslinks. It is intended for non-cervical spine stabilization in skeletally mature patients as an adjunct to fusion for conditions including degenerative disc disease, spondylolisthesis, trauma, spinal stenosis, curvatures, tumor, pseudarthrosis, and failed previous fusion.

The LOCK-IN system is manufactured from Ti-6Al-4V ELI titanium alloy with polyaxial screw design available in standard or spondylolisthesis head configurations. Expandable screws are designed to increase pullout strength compared to similarly sized conventional screws. Minor differences in component geometry and size offerings exist compared to predicates but are addressed through performance testing.

ASTM F543 (pedicle screw pull-out, driving torque, and torsional testing); ASTM F1717 (static/compressive bending and torsional testing); ASTM F2193 (static and dynamic cantilever bending); ASTM F1798 (tulip disassociation testing). Additionally, expandable screw reversibility characterization testing and cadaver pullout comparative performance studies were performed.

The LOCK-IN system demonstrates substantial equivalence because it shares the same intended use (posterior non-cervical fusion adjunct), indications for use, and design function as the predicate EBI Omega 21 System. Non-clinical testing across multiple ASTM standards shows the subject device performs equivalently to the predicate, and minor geometric and size differences are supported by comparison to additional cleared technological predicates in the same device class.