A Biomechanical Comparative Study Of Single-tunnel Double-bundle And Single-bundle Anterior Cruciate Ligament Reconstruction

ObjectivesTo compare the stability of the knee after single-tunnel double-dundle and single-bundle anterior cruciate liagament reconstructions.Methods6 formalin-soaked specimens of the human knee which retaining joint capsule and surrounding ligaments complete weredo the single-tunnel double-dundle and single-bundle anterior cruciate liagament reconstructions, then using the MTS-858 test system to investigates the kinematic response of knee joint under an anterior tiabial load(134N) and rotating load (5 N·m internal rotation of tibia) when the knee flexion 0°, 15°, 30°, 60°, 90°. Each knee was tested sequentially under 4conditions: (1) anterior cruciate ligament intact, (2) anterior cruciate ligament deficient, (3) single-tunnel double-bundle anterior cruciate ligament reconstruction (4) single-bundle anterior cruciate ligament reconstruction. The single-tunnel double-bundle and single-bundle all using double quadrupled hamstring tendon graft.Results(1) anterior tiabial load: single-tunnel double-bundle anterior cruciate ligament reconstruction closely restored the intact knee anterior-posterior stability to normal when knee flexion at 30°, 60°, 90°(P >0.05),the anterior tibial translations is smaller than single-bundle anterior cruciate ligament reconstruct when knee flexion at 30°, 60°(P <0.05). (2) rotating load: single-tunnel double-bundle anterior cruciate ligament reconstruction closely restored the intact knee rotating stability to normal when knee flexion at 0°, 60°(P >0.05),and decrease 1.97±0.60°at 90°flexion(P <0.05). The internal rotation of tibia is smaller than single-bundle anterior cruciate ligament reconstruct when knee flexion at 60°, 90°(P<0.05).ConclusionsThe single-tunnel double-bundle can better restore anterior-posterior stability and rotating stability to the intact level compared with single-bundle anterior cruciate ligament reconstruction.