N22 EZ Glenosphere

The N22 EZ Glenosphere is a titanium alloy reverse shoulder prosthesis component designed for patients with severely deficient rotator cuff who need primary or revision total shoulder replacement. It is used as part of the InSet Reverse Total Shoulder System to relieve pain and disability, particularly in patients with suspected sensitivity to cobalt-chromium alloys.

The device uses titanium alloy (Ti-6Al-4V per ASTM F136) with nitrogen ion implantation surface hardening treatment instead of the cobalt-chromium substrate of the predicate. It maintains identical dimensional specifications, increased articular surface roughness, and a radiused distal end on the male Morse taper. All associated components are Ti-6Al-4V with porous titanium coating (ASTM F67) on the humeral stem and baseplate.

ASTM F136 (titanium alloy), ASTM F75 (cobalt-chromium alloy reference), ASTM F67 (porous titanium coating). Testing conducted per FDA guidance and relevant standards including taper disassembly, fretting/corrosion, pin-on-disk testing, and cadaver design validation.

The N22 EZ Glenosphere is substantially equivalent to the InSet Reverse Total Shoulder System (K210533) predicate because it has identical intended use, same fundamental operating principles, compatible fixation methods, and identical sterilization and compatibility characteristics. The titanium alloy substitution for cobalt-chromium does not raise different safety or effectiveness questions, as the surface hardening treatment was previously FDA-cleared and bench testing using predicate acceptance criteria demonstrates equivalence.