Tunnel Widening After Anatomic Double-Bundle and Mid-Position Single-Bundle Anterior Cruciate Ligament Reconstruction

Prospective Comparisons of Femoral Tunnel Enlargement With 3 Different Postoperative Immobilization Periods After Double-Bundle Anterior Cruciate Ligament Reconstruction With Hamstring Grafts

“…[7][8][9][10][11][12][13][14][17][18][19][20] However, the postoperative knee immobilization periods were different, depending on the authors or institutions; some studies had an accelerated program, whereas other studies had a slow rehabilitation protocol, such as a 1-or 2-week postoperative immobilization period. Therefore the information from our study is clinically of value to clarify the most suitable postoperative immobilization period after doublebundle ACL reconstruction with hamstring grafts.…”

“…Several biological theories have been proposed: synovial fluid propagation within bony tunnels, localized bone necrosis possibly caused by the drilling process due to thermogenic effects that induce a nonspecific inflammatory response, biochemical mediators, and so on. [12][13][14]24 Zysk et al 25 studied synovial fluid samples collected from patients after ACL reconstruction and reported that patients with bone tunnel enlargement had higher concentrations of tumor necrosis factor a, interleukin 6, and nitric oxide, indicating the involvement of these mediators in tunnel enlargement. Kawaguchi et al 20 reported that there was significantly less femoral tunnel enlargement after anatomic double-bundle ACL reconstruction with hamstring grafts than after single-bundle reconstruction; the potential mechanisms were less tension on the tunnel edge due to force sharing by the 2 bundles, less synovial fluid propagation because of a smaller tunnel diameter, and earlier graft remodeling and revascularization because of smaller grafts.…”

“…[4][5][6] However, potential complications associated with postoperative bone tunnel enlargement due to hamstring soft-tissue grafts have been reported. [7][8][9][10][11][12][13][14] The most significant disadvantage after bone tunnel enlargement is difficulty in revision surgery; some cases require additional bone grafting before new bone tunnel creation in the anatomic position. Previously, Shelbourne and colleagues 15,16 introduced the accelerated rehabilitation protocol, and this protocol extensively contributed to reducing the incidence of arthrofibrosis and loss of motion, thus improving functional outcomes.…”

Different Techniques of ACL Reconstruction: Guidelines

“…For a completely torn ACL, the tunnels should be located in the center of the femoral and tibial insertion zone (Achtnich et al 2013). An important issue concerning anatomical ACL reconstruction is the drilling technique.…”

“…Anatomical ACL reconstruction means that the tunnels must be located within the original insertions of the anterior cruciate ligament (Bedi and Altchek 2009;Achtnich et al 2013;Petersen et al 2013) (Fig. 2).…”