03/31/2026
The study that changed the conversation about universal knees.
Researchers evaluated modern symmetrical vs. asymmetrical TKA designs in a head-to-head retrospective review.
The Setup: • 225 patients (246 knees) - Modern Universal (Klassic®) • 235 patients (236 knees) - Asymmetric (Vanguard) • Minimum 1-year follow-up • Radiographic and clinical outcomes
The Results:
📉 Patellar Tilt: Modern Universal showed SIGNIFICANTLY less patellar tilt than the asymmetric design (P < 0.0001)
📊 Patient-Reported Outcomes: • PROMIS Physical Function: 43.5 vs 41.1 (ns) • PROMIS Physical Health: 48.2 vs 46.7 (ns)
• PROMIS Mental Health: 53.3 vs 51.8 (ns) • KOOS JR: 74.5 vs 78.4 (ns)
🔧 Complications: • Manipulation under anesthesia: 6.1% vs 4.2% (ns) • Reoperation: 3.7% vs 3.0% (ns) • Infection: 1.7% vs 1.7% (ns)
Translation: Equivalent safety profile.
The Conclusion: "The symmetrical femoral design demonstrated similar PROs and outcomes to an asymmetrical design. Despite some concern that patellar tracking could be worse in a symmetrical implant, the modern symmetrical TKA design demonstrated less patellar tilt and overall appears to perform clinically similarly to an asymmetric anatomic design."
What this means: Universal geometry + modern features = clinical performance that meets or exceeds asymmetric designs.
https://info.tjoinc.com/modern_sym_vs_asym