Is the bare spot a consistent landmark for shoulder arthroscopy? A study of 20 embalmed glenoids with 3-dimensional computed tomographic reconstruction.
OBJECTIVE
Our aim was to test a published methodology for arthroscopically quantifying glenoid bone loss for its dependability in a cadaver-based anatomic study with 3-dimensional (3-D) computed tomographic (CT) reconstructions of 20 embalmed glenoids.


METHODS
Manual macroscopic measurements were made in a standardized fashion. In addition, we marked the center of the visible bare spot in 20 embalmed glenoids with a titanium pin. The shoulder joints were carefully selected for intact rotator cuff, missing capsule-labral deficiency, and absence of severe cartilage degeneration. 3-D reconstructed CT scans were evaluated for consistency of the bare spot.


RESULTS
The mean distance from the bare spot to the anterior margin measured manually was 10.9 mm (CT-based, 13.9 mm), to the posterior margin 13.7 mm (CT-based, 16.4 mm), and to the inferior margin 9.7 mm (CT-based, 15.1 mm). Distances were significantly different.


CONCLUSIONS
The bare spot did not prove its consistency in 20 carefully selected specimens. Therefore, we conclude that this methodology is not a reliable way to intraoperatively determine bony glenoid deficiency.


CONCLUSIONS
We recommend preoperative bilateral CT scans for evaluation of bony glenoid deficiency for exact quantification of the bone loss.
Kralinger
Franz
F
Department of Trauma Surgery and Sports Medicine, Innsbruck Medical University, Innsbruck, Austria. F.Kralinger@uibk.ac.at
Aigner
Felix
F
Longato
Stefano
S
Rieger
Michael
M
Wambacher
Markus
M
D000368:Aged; D000369:Aged, 80 and over; D000886:Anthropometry; D001182:Arthroscopy; D001858:Bone Nails; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D012540:Scapula / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed