Les longueurs intra-articulaires des greffons à double faisceau peuvent changer pendant la flexion du genou : mesures peropératoires lors de reconstructions anatomiques du ligament croisé antérieur

Abstract Background The lengths of the anteromedial bundle (AMB) and posterolateral bundle (PLB) change during knee motion during double-bundle anterior cruciate ligament (ACL) reconstruction. However, the actual intra-articular graft length would be affected by the bone tunnel position and tunnel creation angle during ACL reconstruction. The aim of this study was to investigate the intra-articular length change of the AMB and PLB in patients who underwent anatomic double-bundle ACL reconstruction. Hypothesis We hypothesized that the PLB would show a more dynamic length change pattern than the AMB during knee flexion at ACL reconstruction. Methods Thirty-two patients (16 men and 16 women) who had isolated ACL injuries with intact menisci were investigated. Anatomic double-bundle ACL reconstructions were performed using semitendinosus tendon autografts at a mean age of 30.6 years. The graft and tunnel lengths were measured intraoperatively. Intra-articular graft lengths and length changes were calculated at 0° and 90° of knee flexion during ACL reconstruction. Intraoperative data were collected prospectively, and analyses were performed retrospectively. Results The intra-articular length of the AMB at 0° of knee flexion was 28.1 ± 5.5 mm. At 90° of knee flexion, the AMB intra-articular length decreased to 25.6 ± 4.8 mm. The intra-articular length of the PLB decreased to 17.7 ± 4.6 mm at 90° of knee flexion compared to 22.0 ± 4.2 mm at 0° of knee flexion. Changes in the intra-articular graft length during knee flexion were detected more in the PLB (4.1 mm) than in the AMB (2.0 mm, p = 0.01). Discussion This study demonstrated that the intra-articular length change of the PLB during knee motion was larger than that of the AMB in anatomic double-bundle ACL reconstructions with semitendinosus tendon autografts and suspensory femoral fixation devices. Level of evidence IV ; retrospective cohort study.