Cervical Spine Truss System - Stand Alone (CSTS-SA)

The Cervical Spine Truss System – Stand Alone (CSTS-SA) is an intervertebral body fusion device indicated for skeletally mature patients with degenerative disc disease of the cervical spine at one or two contiguous levels. The device uses an open-architecture truss design made from Ti6Al4V alloy and is placed anteriorly at C2–T1 disc levels with autograft or allogeneic bone graft, supplemented with two titanium alloy screws or fixation anchors for bony fixation.

The device is an open-architecture truss design manufactured via 4WEB's additive manufacturing process, providing hierarchical surface roughness and structural support with open space for bone ingrowth and fusion. This submission updates the existing CSTS-SA offering with an additional footprint and lordotic angle option. The device is made from Ti6Al4V alloy and available in various sizes.

ASTM F2077 (static and dynamic compression, shear, and torsion testing); screw pushout testing; expulsion testing per industry standard; ASTM F2119 (MR image artifact); ASTM F2182 (MR-induced heating); ASTM F2213 (MR-induced torque); and ASTM F2051 (MR-induced displacement force). Validated finite element analysis was also performed.

The CSTS-SA is substantially equivalent to its primary predicate (K223362) and reference predicates (K203065 and K231739) because the devices share the same indications for use, materials, function, and design principles. Performance testing demonstrates sufficient strength, and finite element analysis confirmed the new worst-case device is not worse than previously tested variants. The comparisons in regard to materials, function, sizes, and testing raise no new questions of safety or effectiveness.