Endoscopic fixation of a double-looped semitendinosus and gracilis anterior cruciate ligament graft using bone mulch screw

Surgeons are switching to the four-bundled hamstring graft, composed of double-looped semitendinosus and gracilis tendons (DLSTG), to replace the torn anterior cruciate ligament. Mechanically, the DLSTG is superior; it is twice as strong and stiffer than a patella tendon graft, and the four bundles share load and mimic the function of the anteromedial and posterolateral bands of the native anterior cruciate ligament. Morbidity from tendon removal is minimal and by 3 months soreness disappears and isometric knee flexion strength returns to normal. It is safe for the patient to undergo aggressive rehabilitation without a brace and to return to sports activities at 4 months when the knee is reconstructed with a DLSTG graft. This report describes the rationale and technique for implanting the DLSTG in a femoral tunnel using rigid fixation instead of a compliant suture bridge. Fixation is achieved by looping the tendons over a post (Bone Mulch Screw) inside the femoral tunnel. The strength, stiffness, and biologic bond of the graft is enhanced by compaction of bone into the femoral tunnel thorugh a bore in the Bone Mulch Screw.