Loss of the sclerotic line of the glenoid on anteroposterior radiographs of the shoulder: a diagnostic sign for an osseous defect of the anterior glenoid rim.
BACKGROUND
The integrity of the glenoid defines the surgical treatment in anterior shoulder instabilities. The reliability of plain radiographs to detect anterior glenoid rim deficiencies was determined.


METHODS
The anterior sclerotic glenoid line (SGL) was assessed on anteroposterior radiographs of 86 shoulders (34 anterior instabilities, 15 posterior instabilities, 37 stable) and compared with computed tomography (CT) scans (gold standard). A loss of the SGL (LSGL) was defined as a positive LSGL sign.


RESULTS
On CT scans, 25 of 34 shoulders (74%) with anterior instabilities showed a defect of the anterior glenoid rim. No defects were found in shoulders without anterior instabilities. LSGL correctly predicted an anterior glenoid rim lesion in 16 (examiner A) or 14 (examiner B) of the 25 anterior instabilities (sensitivity, 64% and 56%), without a false-positive diagnosis (specificity, 100%).


CONCLUSIONS
The LSGL on anteroposterior radiographs is a moderately sensitive but highly specific finding for anterior glenoid rim defects.


METHODS
Level 4; Diagnostic study, case control study.
Jankauskas
Linas
L
Department of Orthopaedics, University of Zurich, Uniklinik Balgrist, Zurich, Switzerland.
Rüdiger
Hannes A
HA
Pfirrmann
Christian W A
CW
Jost
Bernhard
B
Gerber
Christian
C
D000293:Adolescent; D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000000981:diagnostic imaging* / Q000209:etiology / Q000473:pathology; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011336:Probability; D012016:Reference Values; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012783:Shoulder Dislocation / Q000000981:diagnostic imaging / Q000209:etiology / Q000473:pathology; D012785:Shoulder Joint / Q000000981:diagnostic imaging* / Q000473:pathology*; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055815:Young Adult