Arthroscopic ACL Reconstruction with Hamstring Tendons
Anterior cruciate ligament (ACL) reconstruction is commonly performed to restore knee stability in patients with ACL tears. Autograft options include bone-patellar tendon-bone (BPTB) and hamstring tendons. Hamstring grafts have advantages of less donor site morbidity but require secure fixation.
A quadrupled semitendinosus/gracilis (ST/G) graft provides strength nearly 250% greater than the native ACL.1 High stiffness approaches that of BPTB grafts. The larger cross-sectional area facilitates vascular ingrowth. Hamstring grafts avoid extensor mechanism disruption seen with BPTB harvest.
The semitendinosus and gracilis are harvested through an incision over the pes anserinus. After detachment, the tendons are prepared as a quadrupled graft. Tibial and femoral tunnels are drilled in the native ACL footprint. On the femur, transverse fixation with a cortical device like the Bio-TransFix cross-pin provides maximal graft security. Tibial fixation uses an interference screw with a sheath to compress the graft.
The secure graft fixation allows for accelerated rehabilitation with early weightbearing, range of motion, and strengthening. Unrestricted return to sports is typically by 4-6 months.
Prospective randomized trials show comparable subjective outcomes, stability, and complications between hamstring and BPTB grafts.2,3 BPTB reconstruction results in higher rates of anterior knee pain and quadriceps weakness. Return to sport may be delayed compared to hamstrings.
Premature tendon amputation can occur if fascial bands are not released during harvest. Short grafts can be augmented with suture fixation material. Adequate fixation strength minimizes concerns for graft pullout or failure. Tunnel expansion occurs more with hamstrings but does not affect outcomes.
Quadrupled ST/G ACL reconstruction with modern fixation techniques provides comparable outcomes to BPTB grafts. Hamstring grafts offer benefits of less donor site morbidity and quicker recovery. Secure fixation enables accelerated rehabilitation protocols.
1. Noyes FR, Butler DL, Grood ES, et al. Biomechanical analysis of human ligament grafts used in knee-ligament repairs and reconstructions. J Bone Joint Surg Am. 1984;66(3):344-352.
2. Freedman KB, D’Amato MJ, Nedeff DD, et al. Arthroscopic anterior cruciate ligament reconstruction: a metaanalysis comparing patellar tendon and hamstring tendon autografts. Am J Sports Med. 2003;31(1):2-11.
3. Xie X, Liu X, Chen Z, Yu Y, Peng S, Li Q. A meta-analysis of bone-patellar tendon-bone autograft versus four-strand hamstring tendon autograft for anterior cruciate ligament reconstruction. Knee. 2015;22(2):100-110.