"There are two glenoid ossification centres - superior and inferior 5. The typical pattern in glenoid hypoplasia involves the failure of the inferior glenoid epiphysis to ossify properly. Depending on the degree of development, there is variably deficiency of the inferior glenoid, compensatory hypertrophy of the articular cartilage/labrum, and variable glenoid retroversion relative to the scapular body/neck."