A patellar prosthesis has a dome and a body having a central post and an outwardly facing surface tapering toward said dome in a direction extending away from said central post. A plurality of cavities are formed in said body outwardly facing surface. The cavities include an undercut wall for retention...http://www.google.fr/patents/US5383937?utm_source=gb-gplus-shareBrevet US5383937 - Recessed patellar prosthesis
