Is the Bare Spot a Good Landmark for Arthroscopic Evaluation of Anterior Glenoid Bone Loss?
Chusak Kijkunasathian MD1, Chalermchai Limitlaohaphan MD1, Nadphorn Saengpetch MD1, Porncharn Saitongdee MD2, Krai Meemon PhD2, Chinnawut Suriyonplengsaeng MD2
Affiliation : 1 Department of Orthopaedics, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand 2 Department of Anatomy, Faculty of Science, Mahidol University, Bangkok, Thailand
Objective : Glenoid defect is an important factor of consideration in determining appropriate surgical treatment for anterior
shoulder instability, so precise assessment is necessary. The glenoid fossa bare spot has been reported to be a useful landmark
during arthroscopic examination, although there are some controversies. The objective of the present study is to determine
whether the bare spot is located in the center of the glenoid and thus the extent to which it can be used as a landmark.
Materials and Methods : The distance from the center of the bare spot to the anterior, posterior, superior, and inferior rim of
the glenoid were measured in 40 male and 26 female specimens.
Results : The average glenoid length was 36.1 mm superoinferiorly and 27.2 mm anteroposteriorly. However, both the
vertical and horizontal length of the glenoid was significantly smaller in females than in males (p-value <0.01). The average
anterior and posterior glenoid length was 13.2 mm in females versus 13.5 mm. The anterior glenoid length was significantly
shorter than the posterior length in females (p-value = 0.02), but there was no significant difference in males (p-value = 0.22).
Conclusion : The anterior glenoid length is shorter than the posterior in females. The posterior glenoid length may be a useful
reference in evaluating bone loss of the anterior glenoid rim in males, but may not be useful in females.
Keywords : Anterior glenoid defect, Bare spot, Arthroscopic evaluation
