Scot Elliot Campbell MD, Presenter: Nothing to Disclose

Robert Michael DeWitt MD, Abstract Co-Author: Nothing to Disclose

Kenneth L. Cameron, Abstract Co-Author: Nothing to Disclose

Adrianne Kamara Thompson MD, Abstract Co-Author: Nothing to Disclose

Brett D. Owens, Abstract Co-Author: Nothing to Disclose

A cleft at the chondrolabral junction of the posteroinferior glenoid has been described on cadaver and CT-arthrography studies, and has been suggested to represent an anatomic variation. The purposes of this study were to determine the prevalence of a posterior chondrolabral cleft in a young, healthy population, to determine if it was associated with anatomic variations of the anterior labrum or osseous glenoid, and to determine its clinical significance.

A prospective cohort study was performed to identify risk factors for shoulder instability. Baseline assessment included clinical history and MRI of each shoulder. Each patient was followed prospectively for the development of shoulder instability for the next four years. A musculoskeletal radiologist blinded to history and outcomes evaluated each MRI for a high signal intensity cleft at the posterior chondrolabral junction, anatomic variations of the anterosuperior labrum (e.g. sublabral foramen), and glenoid hypoplasia. Univariate stastical analysis was performed to identify associations with pain, history of surgery, anterior labral variations, glenoid hypoplasia, history of glenohumeral instability, or prospective glenohumeral instabiity on follow-up.

Mean age was 18.8±1.0 years for males and 18.7±0.9 years for females. There were 1264 shoulder MRI studies, 129 female (10.2%), 1135 male (89.8%). A posterior chondrolabral cleft was present in 114/1264 (9%). There was no association with pain, history of surgery, or anterior labral variation on MRI. Subjects with posterior chondrolabral cleft were 18.5 times more likely to have glenoid hypoplasia than those without a cleft (p<0.001). Subjects with a history of glenohumeral instability were twice as likely to have a posterior chondrolabral cleft on MRI (p=0.015). Subjects who experienced a glenohumeral instability event during the study follow-up were nearly three times as likely to have had a posterior chondrolabral cleft on MRI at baseline (p=0.005).

Posterior chondrolabral cleft is a common finding on MRI, and is highly associated with glenoid hypoplasia. The presence of a posterior chondrolabral cleft is associated with higher risk of shoulder instability events.

The presence of a posterior chondrolabral cleft on MRI indicates a higher risk of shoulder instability events.

Campbell, S, DeWitt, R, Cameron, K, Thompson, A, Owens, B, Posterior Chondrolabral Cleft: Association with Labral and Glenoid Variants and Clinical Significance.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12029082.html