Analysis of modified double-bundle anterior cruciate ligament reconstruction with implantless fixation on tibial side.

PURPOSE

To avoid potential problems of double-bundle anterior cruciate ligament reconstruction (ACLR), various modifications have been reported. This study analyzed a novel technique of modified double-bundle (MDB) ACLR without implant on tibial side in comparison to single-bundle (SB) ACLR.

METHODS

Eighty cases of isolated anterior cruciate ligament tear (40 each in SB group or MDB group) were included. SB ACLR was performed by outside in technique with quadrupled hamstring graft fixed with interference screws. In MDB group, ACLR harvested tendons were looped over each other at the center and free ends whipstitched. Femoral tunnel was created by outside in technique. Anteromedial tibial tunnel was created with tibial guide at 55°. The anatomic posterolateral aiming guide (Smith-Nephew) was used to create posterolateral tunnel. With the help of shuttle sutures, the free end of gracillis was passed through posterolateral tunnel to femoral tunnel followed by semitendinosus graft through anteromedial tunnel to femoral tunnel. On tibial side the graft was looped over bone-bridge between external apertures of anteromedial and posterolateral tunnel. Graft was fixed with interference screw on femoral side in 10° knee flexion. International Knee Documentation Committee (IKDC), Tegner score, Pivot shift and knee laxity test (KLT, Karl-Storz) were recorded pre- and post-surgery. At one year magnetic resonance imaging (MRI) was done. Statistical analysis was done by SPSS software.

RESULTS

Mean preoperative KLT reading of (10.00 ± 1.17) mm in MDB group improved to (4.10 ± 0.56) mm and in SB group it improved from (10.00 ± 0.91) mm to (4.80 ± 0.46) mm. The mean preoperative IKDC score in MDB group improved from (49.49 ± 8.00) to (92.5 ± 1.5) at one year and that in SB group improved from (52.5 ± 6.9) to (88.4 ± 2.6). At one-year 92.5% cases in MDB group achieved their preinjury Tegner activity level as compared to 60% in SB group. The improvement in IKDC, KLT and Tegner scale of MDB group was superior to SB group. MRI confirmed graft integrity at one year and clinically at 2 years.

CONCLUSION

MDB ACLR has shown better outcome than SB ACLR. It is a simple technique that does not require fixation on tibial side and resultant graft is close to native ACL.