Article Abstract

Behind-remnant approach for anatomic anterior cruciate ligament reconstruction

Authors: Hideyuki Koga, Takeshi Muneta


A newly proposed femoral tunnel creation concept, a behind-remnant (BR) approach, for remnant-preserving double-bundle (DB) anterior cruciate ligament (ACL) reconstruction, was introduced. In this technique, femoral tunnels are created based on the arthroscopic observation from behind the ACL remnant, using the remnant fold at the ACL femoral attachment and posterior cartilage margin as landmarks, without any removal of the remnant tissue. Graft tension changes and femoral tunnel position of the anteromedial bundle (AMB) and posterolateral bundle (PLB) in the BR approach (BR group, 23 patients) were compared with those in the control group (25 patients). Two-year clinical results in 48 patients who had DB ACL reconstruction using BR approach were evaluated. During passive knee movement, the control group indicated reciprocal tension pattern between the AMB and PLB. The PLB generally showed greater tension in extension than the AMB. The BR group indicated equivalent tension pattern between the AMB and PLB. The AM tunnel position was significantly more posterior in the BR group with the smaller variances than in the control group. During 2-year follow-up, there was 1 graft tear of the reconstructed ACL. Average KT measurements improved from 6.1 mm preoperatively to 0.6 mm. Lachman test became negative in all cases. Pivot shift result was also improved, although 6 cases had residual pivot shift test. Average Lysholm score was improved from 79 preoperatively to 98, and average time required to return to athletic activities was 8 months. The BR approach made femoral tunnel creation possible with better reproducibility. More posterior tunnel creation using BR approach indicated similar tension pattern between the AMB and PLB. Short-term clinical results after remnant-preserving DB ACL reconstruction using BR approach were satisfactory in both subjective and objective findings.