Skulderproteseanordning

The invention concerns a shoulder prosthesis assembly comprising a meta-glenoid element ( 7 ) formed by a plate ( 13 ) provided with a central tubular block ( 14 ) an anchoring members in the glenoid cavity ( 3 ), and a glenoid sphere ( 9 ) designed to top the metaglenoid element and provided with an axial screw ( 35 ) screwed into said pin; the glenoid sphere has an articulated surface ( 11 ) designed to co-operate with a cup of an associated humeral prosthesis ( 2 ); said assembly comprises means ( 16, 45, 46; 51, 50, 49 ) guiding the glenoid sphere adapted to facilitate its being fixed on the meta-glenoid element; said means comprise a pin ( 46 ) adapted to be slotted into the tubular block ( 14 ) and into an axial passage of the screw ( 35 ); the glenoid sphere ( 9 ) is thus guided by being slid on the pin ( 46 ) until the screw ( 35 ) is inserted precisely into the axis of the tubular block ( 14 ), wherein it can be screwed without any risk of damaging the thread on the screw and the internal thread of the block. Advantageously, the free end ( 48 ) of the screw ( 35 ) can likewise be bevelled to facilitate its being inserted in the block ( 14 ) without damaging the threads. The inventive arrangement is particular useful considering the difficulties encountered by the surgeon for correctly positioning the glenoid sphere ( 9 ) relative to the meta-glenoid element ( 7 ) owing to lack of visibility.