Convertible glenoid

Abstract

A glenoid system (100) includes a baseplate (102) configured to attach to a glenoid cavity of a patient. In a primary configuration, a biocompatible plastic liner (332) can snap into a circumferential groove (120) on the baseplate, to attach to a lateral-facing surface (104) of the baseplate, at one or more locations around the groove. In a reverse configuration, a glenosphere (544, 644) can attach to an adapter (542, 642), which in turn can attach to the lateral-facing surface of the baseplate. The adapter can introduce lateral and/or angular offsets between the baseplate and the glenosphere, which can correct for unwanted offsets or inclinations. A middle peg extension (752) can screw onto a medial end of the middle peg (114), which can offer different combinations of peg length and peg material. The baseplates can be made available in various discrete sizes, each of which has the same distance between the middle peg and an inferior screw hole (112).

The claimed invention is: 
     
         1 . A glenoid system, comprising:
 a baseplate configured to attach to a glenoid cavity of a patient,
 the baseplate defining a lateral-facing surface extending from a superior end of the baseplate to an inferior end of the baseplate, the lateral-facing surface facing laterally when the baseplate is attached to the glenoid cavity, 
 the baseplate defining a superior hole through the lateral-facing surface proximate the superior end of the baseplate, 
 the baseplate defining an inferior hole through the lateral-facing surface proximate the inferior end of the baseplate, and 
 the baseplate being coupled to a middle peg at a middle area between the inferior and superior holes, the middle peg extending medially from the baseplate when the baseplate is attached to the glenoid cavity; and 
   an adapter having a first taper,
 the first taper being a male taper sized and shaped to form a taper fit with a recess in the middle peg, 
 the adapter further having a second taper offset from the first taper, and 
 the second taper being size and shaped to form a taper fit with a glenosphere or a glenoid shield.