Abstract
The purpose of the study was to describe the normal anatomy of glenoid labrum. Twenty dry bone scapulas and 19 cadaveric shoulders were examined. Light microscopy was performed on 12 radial slices through the glenoid.
An external capsular circumferential ridge, 7–8mm medial to the glenoid rim marks the attachment of the capsule. A separate internal labral circumferential ridge 4mm central to the glenoid rim marks the interface for the labrum and articular cartilage. A superior-posterior articular facet contains the superior labrum. Two thirds of the long head of biceps arise from the supraglenoid tubercle, the remainder from the labrum. The superior labrum is concave and is loosely attached to the articular cartilage and glenoid rim. In contrast the anterior-inferior labrum is convex, attaches 4mm central to the glenoid rim and has a strong attachment to articular cartilage and bone.
The anatomy of the superior and anteroinferior labrum are fundamentally different. Suture anchor repair of the superior labrum should be 7mm medial to the glenoid rim whereas the anterior-inferior labrum should be repaired to the face of the glenoid. By defining the normal anatomy of the superior labrum, pathological tears can be identified.
Correspondence should be addressed to Associate Professor N. Susan Stott at Orthopaedic Department, Starship Children’s Hospital, Private Bag 92024, Auckland, New Zealand
