Capsulolabral augmentation by blood injection increases the intrinsic stability provided by the glenoid.

Abstract

PURPOSE: To test the hypothesis that the intrinsic stability of the cadaveric glenoid can be augmented by the injection of blood into the labrum. METHODS: The intrinsic stability of 10 fresh frozen cadaveric glenoids was assessed by measuring the balance stability angle. Pretreatment values of 8 directions in each glenoid were obtained. The labrum was then injected with blood freshly drawn from a volunteer. After the injected blood clotted, measurements of the balance stability angle of the 8 directions were again obtained. RESULTS: The mean pre-injection balance stability angle for 7 of the 8 directions were significantly increased by the injection of blood: anterosuperior, from 25 to 35 degrees (p<0.005); anterior, from 27 to 34 degrees (p<0.01); anteroinferior, from 36 to 39 degrees (p<0.005); inferior, from 38 to 41 degrees (p<0.02); posteroinferior, from 35 to 42 degrees (p<0.01); posterior, from 27 to 35 degrees (p<0.0005); and posterosuperior, from 26 to 29 degrees (p<0.005). Cross-sections of injected labra demonstrated a firm clot within the labrum with substantial increases in thickness. CONCLUSION: The intrinsic stability of cadaveric glenoids can be significantly augmented by the injection of blood into the labrum. It is possible that blood injection may be a useful primary or adjunct procedure in the open or arthroscopic management of glenohumeral instability.