The Journal of Shoulder and Elbow Surgery

N. Douglas Boardman III, Richard E. Debski, Jon J.P. Warner, Emin Taskiran, Lisa Maddox, Andreas B. Imhoff, Freddie H. Fu, Savio L-Y. Woo


The structure and stabilizing function of the capsuloligamentous components of the glenohumeral joint have been extensively studied using anatomic dissections, ligament sectioning, and strain gauge analysis techniques. Recent evidence has shown that the superior glenohumeral ligament and coracohumeral ligament are important static stabilizers; however, their role remains controversial. To clarify the function of these two ligaments, we studied their tensile properties using bone-ligament-bone complexes from fresh-frozen shoulders, ten SGHLs and ten CHLs. Each ligament's cross-sectional area was measured and uniaxial tensile testing of each complex was performed. The stiffness, ultimate load, percent elongation, and energy absorbed to failure of each bone-ligament-bone complex were derived from its load-elongation curve. The cross-sectional area of the coracohumeral ligament was significantly greater than that of the superior glenohumeral ligament at their midportions (CHL: 53.7±3.2 mm2 versus SGHL: 11.3±1.6 mm2, p<0.05). Results also reveal significant differences between the tensile properties for the two ligaments, with the coracohumeral ligament possessing greater stiffness (CHL: 36.7±5.9 N/mm versus SGHL: 17.4±1.5 N/mm, p<0.05) and ultimate load (CHL: 359.8±40.3 N versus SGHL: 101.9±11.5 N, p<0.05) than the superior glenohumeral ligament. Our findings confirm that the coracohumeral ligament is an important capsuloligamentous structure at the glenohumeral joint.