Single bundle vs double bundle for anterior cruciate ligament reconstruction evaluated with T2 mapping: A case series

Introduction: ACL reconstruction is needed to restore the stability and biomechanics properties of the injured knee joints in order to reproduce the function of the native ACL. The single-bundle (SB) and double-bundle (DB) techniques are most commonly used to reconstruct the injured ACL. However, its superiority upon each other is still controversial. Presentation of case: This study presented a case series of six patients underwent ACL reconstruction, consisted of three patients with SB ACL reconstruction and three patients with DB ACL reconstruction with further T2 mapping for joint instability evaluation. Only two DB patients showed consistent decreased value in every follow-up. Discussion: ACL tear can generate joint instability. Joint instability is resulted from two mechanisms of relative cartilage overloading. First, there is an abnormal load distribution due to shifting of the center of pressure of the tibiofemoral force, resulting in increased stresses on the articular cartilage of the knee joint. There is also an increase of translation between articular surfaces, resulting in increased shear stresses on the articular cartilage. A trauma of knee joint causes cartilage damage and increased oxidative and metabolic stress of chondrocytes, resulting in chondrocyte senescence acceleration. Conclusion: This case series showed inconsistent results to determine either SB or DB has a better outcome in joint instability, thus further larger studies are needed.