Anterior cruciate reconstruction with bioactive Leeds-Keio ligament (LKII): preliminary report

The scaffold type Leeds-Keio artificial ligament (LK) for ligament reconstruction of the knee provides sufficient strength to require minimal sacrifice of autogenous tissue. This implant works not only as prosthesis but also as scaffold onto which natural tissue grows from the synovium. LK has been in clinical use for anterior cruciate ligament (ACL) reconstruction since 1982, although the operative procedure has been modified and has undergone significant development since that time. Recently, we developed radio frequency-generated glow discharge (RFGGD)-treated LK ligament (LKII, previously indicated as Bio-LK) to improve tissue induction and reported that cell proliferation and cell attachment to artificial fibers increased considerably with this hydrophilic treatment. In this study, we report the findings of reconstructed ACL using LKII, which has been in clinical use since 2003. At reconstruction, LKII was covered with the remnant of the original ACL as much as possible in order to preserve the nerve ending system. Thirteen cases with over 12 months' postoperative history were reviewed. Knee stability was regained after reconstruction without any complications such as joint effusion and chronic synovitis. In one case, postoperative arthroscopy showed that the reconstructed ACL was completely covered with newly formed tissue at 8 weeks postoperatively. Biopsy revealed abundant fibroblasts, collagenous fibers, and vessels around the artificial fibers without marked inflammatory findings. Transmission electron microscope study showed abundant thin collagen fibers, which demonstrated regular orientation to some extent. Fibroblasts were observed with extensive amount of rough endoplasmic reticulum. According to these results, we consider LKII to be superior to LK in tissue induction and maturation.