19
18
To obtain good bone seating, the metaglene should
ideally be positioned on the inferior circular area of the
glenoid. The metaglene central peg should be positioned
in the centre of the inferior circle of the glenoid (This
point is often posterior and inferior to the intersection of
the glenoid axes) (Figure 21).
using these anatomical reference points helps to position
the metaglene as inferior as possible on the glenoid in
order to limit potential bone impingement, while keeping
a secure glenoid implant fixation.
however, radiographic, cT images combined with X-ray
templates and the intra-operative view may indicate a
slightly more superior position, to obtain fixation in good
bone stock and complete sitting of the metaglene on the
bone.
particular attention should be given to metaglene
positioning to achieve optimal glenoid fixation, range of
motion and limit potential bone impingement.
The position must be chosen to obtain maximum contact
with the glenoid surface and to allow secure fixation of
the screws in bone.
posiTioNiNg ThE mETAgLENE
Figure 21
