Background: The aim of the study was to investigate the anatomical characteristics
and symmetry of the bilateral glenoid structures of Chinese people and
to explore the relationship between the glenoid bone structure and recurrent
anterior dislocation.
Materials and methods: The control group included 131 individuals with no
history of shoulder dislocation. The dislocation group consisted of 131 patients
with a history of unilateral shoulder dislocation. All subjects underwent computed
tomography scans. Glenoid shape (pear-shaped, inverted comma-shaped,
oval-shaped), width, height, depth, version angle, area, maximum fitting circle
area and volume were measured.
Results: There was no significant difference in normal bilateral glenoid of Chinese
people (p > 0.05). There were statistically significant differences in depth, height
to width ratio, maximum fitting circle area and shape between the dislocation and
control groups (p < 0.05). Regression analyses showed that the glenoid depth
(odds ratio [OR] 0.48; p < 0.01), the glenoid height to width ratio (OR 28.61;
p < 0.01), the glenoid maximum fitting circle area (OR 1.01; p < 0.01) and the
glenoid shape (p <0.05; pear-shaped OR 0.432; inverted comma-shaped OR
0.954) were associated with anterior shoulder instability. Pear-shaped and inverted
comma-shaped glenoid had lower risk of recurrent anterior shoulder dislocation
compared to oval glenoid. Receiver operating characteristic curve analysis showed
that individuals with anterior shoulder instability had smaller glenoid depth and
larger height to width ratio and the glenoid maximum fitting circle area compared
with the control group.
Conclusions: The normal bilateral glenoids of Chinese people are basically symmetrical.
The glenoid shape, depth, height to width ratio and maximum fitting
circle area are risk factors for recurrent anterior shoulder dislocation. Evaluation
of the glenoid bone structure enables more accurate prediction of the risk of
recurrent shoulder dislocation.