Initia Knee System

The Initia Knee System is a total knee replacement prosthesis consisting of femoral, tibial, and patella components made from cobalt-chromium-molybdenum alloy, titanium alloy, and polyethylene materials. It is intended for patients with painful, disabled knee joints from arthritis or deformity, and is implanted using bone cement in either cruciate-retaining or posterior-stabilizing designs.

The Initia Knee System uses the same materials (Co-Cr-Mo femoral, Ti-6Al-4V baseplate, cross-linked and conventional UHMWPE inserts/patellae), design types (CR and PS), cemented fixation method, and patellar locking mechanism as the predicate A200 Knee System. Minor differences include increased sizing options (11 femoral vs. 9, 10 baseplate vs. 9, 7 tibial inserts vs. 3, 7 patella vs. 5) and slightly different component dimensions, but these raise no new safety or effectiveness questions.

The device complies with ASTM standards for knee prostheses (F2083-21, F1672-14, F1800-12, F3210-22), ISO standards for knee implants (ISO 7207-2), sterilization standards (ISO 11137 series, ANSI/AAMI/ISO 11135:2014), biological evaluation (ISO 10993-1:2018), packaging (ISO 11607 series), and other quality/performance standards including endotoxin testing and accelerated aging protocols.

The Initia Knee System is substantially equivalent to the A200 predicate because it shares identical indications for use, the same or nearly identical materials and design philosophies (CR and PS designs with cemented fixation), and underwent the same non-clinical performance testing (tibial post fatigue, locking mechanism, constraint, contact stress, and patellofemoral subluxation). Although the Initia offers more size options and has slightly different dimensions, verification and validation testing demonstrated these minor design differences do not raise new questions of safety or effectiveness compared to the predicate.