Equinoxe® Shoulder System

The Equinoxe Shoulder System is a reverse total shoulder arthroplasty prosthesis for skeletally mature patients with degenerative glenohumeral joint disease and irreparable rotator cuff deficiency. The proposed submission covers Equinoxe Activit-E Reverse Humeral Liners constructed of highly crosslinked UHMWPE containing vitamin E, used as the bearing surface component in reverse shoulder replacement.

The key technological difference is the material composition: the proposed devices use highly crosslinked UHMWPE with vitamin E (Activit-E), whereas the predicate devices use conventional UHMWPE. There are no changes to geometric design, compatibility, or mechanical features—only the polymer formulation differs.

ISO 10993-1:2018 (biocompatibility), ASTM F1877-05:2010 (wear particle analysis), USP <161> and USP <85> (bacterial endotoxins), ANSI/AAMI ST72 (endotoxins). Additional testing included humeral liner-tray fatigue, disassembly, and Mode I wear testing.

The devices are substantially equivalent because they maintain identical intended use, design features, and indications as the predicate. Although the material differs (Activit-E vs. conventional UHMWPE), both are biocompatible UHMWPE variants with similar mechanical properties. Preclinical testing—fatigue, disassembly, wear, and biocompatibility—demonstrates the material change does not adversely affect safety or performance, and the new formulation does not introduce new failure modes or risks.