Since the introduction of metal-backed tibial components, fracture of the tibial tray has been recognized as an occasional complication. Long-term fol-low-up confirms that this event is uncommon, especially in biologically fixed knee prostheses. We report a case of early fracture of a biologically fixed tibial tray that occurred two years after implantation. Several known risk factors have been identified. Axial malalignment is thought to be the major cause of failure.