Reverse total shoulder arthroplasty (RTSA)
was initially used to manage massive rotator cuff tear
and rotator cuff tear arthropathy. The indications have
been expanded to more complex shoulder problem such
as failed shoulder arthroplasty and proximal humeral
fracture sequelae.
The rising in number of RTSA may lead to
complications unique to the procedure. The mechanical
glenoid baseplate failure is one of the common problems
after RTSA. The loosening of glenoid component can
be prevented by placing the baseplate at the lower part
of glenoid bone so that the inferior screw will achieve
the strongest pull-out strength, enough to resist the
pull-out force of the glenoid component(1). The glenoid
component from western manufacturers may cause an
overhang on the glenoid in Thai patients, and then
lead to screw misplacement and result in the early
loosening of the component.