Biologic and Mechanical Augmentation in Anterior Cruciate Ligament Reconstruction: Fibrin Clot Augmentation of 5-Strand Hamstring Autograft

Hamstring autografts in anterior cruciate ligament reconstruction have an excellent clinical track record, but some patients have hamstring tendons that yield grafts of smaller diameter, which has been shown to be a significant risk factor for worse outcomes and graft failure. Some authors have advocated augmentation with allograft in these patients. Tripling the semitendinosus yields a completely autogenous 5-strand graft with a larger diameter but still of sufficient length. In addition, imaging studies still show signal heterogeneity within grafts, even autografts, after the healing process, which correlates with worse biomechanical properties. Recent animal studies have shown improved incorporation and better remodeling of soft tissue grafts with the use of an endogenous fibrin clot. We present our technique of biologic and mechanical augmentation of hamstring autografts with fibrin clot and a 5-strand graft.