THE CORRELATION BETWEEN FEMORAL INTERCONDYLAR NOTCH VOLUME AND FEMORAL

Purpose

The purpose of this study was to investigate the correlation between femoral intercondylar notch volume and the characteristics of femoral tunnels in anatomical single bundle anterior cruciate ligament (ACL) reconstruction.

Methods

Fifty-one (51) subjects (24 male and 27 female: median age 27: range 15-49), were included in this study. Anatomical single bundle ACL reconstruction was performed in all subjects using a trans-portal technique. Femoral tunnel length was measured intra-operatively. Three-dimensional computed tomography (3D-CT) was taken at pre and post-surgery. The intercondylar notch volume was calculated with a truncated-pyramid shape simulation using the pre-operative 3D-CT image. In the post-operative 3D-CT, the modified quadrant method was used to measure femoral ACL tunnel placement. Statistical analysis was performed to evaluate the correlation between characteristics of the femoral tunnel (length and placement) and femoral intercondylar notch volume.

Results

Femoral tunnel placement was 47.6±10.5% in the high-low (proximal-distal) direction, and 22.6±5.4％ in the shallow-deep (anterior-posterior) direction. Femoral tunnel length was 35.3±4.4cm. Femoral intercondylar notch volume was 8.6±2.1cm3. A significant correlation was found between femoral intercondylar notch volume and high-low (proximal-distal) femoral tunnel placement (Pearson’s coefficient correlation: 0.469, p=0.003). 

Conclusion

Femoral ACL tunnel placement at a significantly lower level was found in knees with large femoral intercondylar notch volume in the trans-portal technique. For the clinical relevance, surgeons can create femoral ACL tunnel low (distal) in the notch where close to the anatomical ACL footprint in the knees with large femoral intercondylar notch volume.