Glenoid version and inclination are risk factors for anterior shoulder dislocation.
HYPOTHESIS
Although the contribution of the capsuloligamentous structures and dynamic muscle balance to shoulder stability has been well documented, the role of the osseous anatomy of the glenoid has not been thoroughly evaluated. This study investigated glenoid version and inclination in patients with a documented anterior shoulder dislocation and compared it with a control group. We hypothesized that patients with a prior anterior dislocation would have more anterior version and increased inferior inclination of the glenoid.


MATERIALS AND METHODS
Patients aged younger than 40 years who underwent arthroscopic shoulder stabilization (study group) were compared with patients (control group) who had previously undergone magnetic resonance imaging (MRI) for a different shoulder condition. Version was measured on axial images, and inclination was measured on coronal images of a T2-weighted spin-echo scan. The MRIs of 128 study group patients (mean age, 24.5 ± 8.6 years) with a confirmed traumatic anterior shoulder dislocation were compared with the MRIs of 130 control group patients (mean age, 30.9 ± 7 years).


RESULTS
The mean version in the study group was -1.7° ± 4.5° (retroversion); the mean inclination was 1.6° ± 5.9° (inferior). The mean version in the control group was -5.8° ± 4.6° (retroversion); the mean inclination was -4.0° ± 6.8° (superior). The between-group differences were significant for version (P = .00001) and inclination (P = .00001).


CONCLUSIONS
The results of this study strongly suggest that glenoid version and inclination are significantly increased in patients with established anterior shoulder instability compared with a matched control group.
['Hohmann|Erik|E|', 'Tetsworth|Kevin|K|']
D000293:Adolescent D000328:Adult D001182:Arthroscopy D005260:Female D006801:Humans D008279:Magnetic Resonance Imaging D008297:Male D012307:Risk Factors D012783:Shoulder Dislocation D012785:Shoulder Joint D055815:Young Adult
glenoid version risk factor Anterior shoulder dislocation glenohumeral subluxation glenoid inclination shoulder injury