TRANSTIBIAL VERSUS INDEPENDENT FEMORAL TUNNEL DRILLING TECHNIQUES FOR ARTHROSCOPIC ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION EVALUATION OF FEMORAL APERTURE POSITIONING

Background: Although numerous clinical and cadaveric studies have compared transtibial (TT) versus tibial independent (TI) either anteromedial (AM) portal or Outside-in (OI) drilling techniques regarding anatomic femoral tunnel aperture placement in single bundle anterior cruciate ligament reconstruction (ACLR), there is no consensus on which technique offers the best anatomic position according to footprint position.
Aim of the Work: The aim of this study is to conduct a systematic review and meta-analysis for studies comparing the anatomical position of femoral tunnel aperture in single bundle ACLR using TI and TT techniques. Methods: (PubMed, Cochrane library and Google Scholar) were searched for relative studies that evaluated femoral tunnel aperture position in patients and cadavers underwent arthroscopic single bundle ACLR. Meta-analyses were performed to pool 28 studies included in 15 outcomes measuring femoral tunnel aperture position by estimating the mean differences and their 95% confidence intervals from mean and standard deviation for each study. Results: 48 clinical and cadaveric studies compared femoral tunnel aperture position between TT and TI (AM and OI) techniques were obtained for final research. In these studies, 2384 clinical and cadaveric knees underwent arthroscopic single bundle ACLR, we qualitatively assessed the femoral aperture position in all 48 studies showing that the difference between TI and TT was non significant except in the direction perpendicular to Blumensaat's line (BL), but with low mean difference and anteroposterior (AP) anatomical axis. Conclusions: There was non-significant difference between TI and TT technique regarding placing femoral aperture position closer to footprint position. There was non-significant difference in femoral aperture sagittal plane position along BL or along (proximal-distal) PD axis. Regarding femoral aperture coronal plane placement in the axis perpendicular to BL; modified TT technique improved the femoral aperture position in this axis. While regarding femoral aperture placement in the anteroposterior (AP) anatomical axis; TI technique placed femoral aperture significantly more posterior than TT technique, this was proper position regarding anatomic ACLR, while according to the recent concept of ACL femoral footprint, this might be improper position."