29
28
metaglene Anterior-posterior cross section
polyaxial Locking or Non-locking screws
17˚
±10˚
The surgeon may use locking or non-locking screws in
the anterior or posterior holes. Both types of screws will
allow an angulation of up to ±10°, but
not
in a direction
convergent to the central peg axis to avoid conflict with
the peg when drilling (Figure 44).
use the 2.5 drill bit with the drill guide to set the most
appropriate angle for ensuring that each screw is located
in good bone stock (Figure 45).
The preferred position is usually chosen by palpating the
anterior and posterior aspects of the scapula as well as
examining the X-rays and cT scans. Drill in the direction
of the central glenoid vault in an attempt to maximise the
anterior and posterior screw lengths, in a direction parallel
to or divergent from the central peg.
ANTERioR AND posTERioR mETAgLENE
scREW pLAcEmENT
Figure 44
Figure 45
