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DEFiNiTivE gLENosphERE FiXATioN
sTANDARD gLENosphERE
Standard Glenosphere
Engage the 3.5 mm cannulated hex screwdriver in the
implant glenosphere. slide the glenosphere on the 1.5
mm guide pin until it is in contact with the metaglene
(Figure 74). proper alignment between the glenosphere
and metaglene is absolutely essential to avoid cross
threading between the components.
proper alignment leads to smooth thread engagement
and easy screwing. if the glenosphere seems difficult to
thread onto the metaglene, do not force engagement
but re-align the components. if necessary remove the
inferior retractor or improve the capsular release. it is also
important to check that there is no soft tissue between
the metaglene and glenosphere.
When accurate thread engagement is obtained and after
a few turns, remove the guide pin to avoid stripping in the
screwdriver.
Tighten until the scapula begins to rotate slightly in a
clockwise direction in response, meaning that the glenoid
bearing is closing on the taper of the metaglene.
obtain further impaction of the junction by gently
hammering the glenosphere with the glenosphere
impactor a minimum of three times, using at least a
700g hammer (Figure 75). Then tighten the glenosphere
central screw again. care should be taken to ensure that
the glenoid bearing is fully locked onto the metaglene.
The gentle hammering procedure and screw tightening
can therefore be repeated if necessary until further screw
tightening, without excessive torque, is not possible.
Figure 74
Figure 75
