In vivo evaluation of femoral and tibial graft tunnel placement following all-inside arthroscopic tibial inlay reconstruction of the posterior cruciate ligament.

BACKGROUND

The arthroscopic all-inside tibial inlay technique represents a novel procedure for posterior cruciate ligament (PCL) reconstruction. However, in vivo investigations that evaluate the accuracy of this technique regarding anatomic graft tunnel placement are few. The objective of this study was to analyse the femoral and tibial tunnel apertures using computed tomography (CT) and compare these findings to recommendations in the literature.

METHODS

CT scans were obtained in 45 patients following single-bundle PCL reconstruction. The centres of the tibial and femoral tunnel apertures were correlated to measurement grid systems used as a radiographic reference.

RESULTS

The centre of the femoral tunnel aperture was located at 42.9% ± 9.4% of the total intercondylar depth and at 12.9% ± 7.2% of the total intercondylar height. The angle α for the femoral tunnel position was measured at 64.2° ± 10.0°. The centre of the tibial tunnel aperture was found at 51.8% ± 4.1% of the total mediolateral diameter of the tibial plateau. The superoinferior distance of the tibial tunnel aperture to the joint line was 9.6 mm ± 4.4 mm on frontal and 9.3 mm ± 3.4 mm on sagittal 3D-CT scans. The distance of the tibial tunnel aperture to the former physis line averaged to 0.8 mm ± 3.4 mm. Comparison to the corresponding reference values revealed no statistically significant difference.

CONCLUSION

Arthroscopic tibial inlay reconstruction is an efficient procedure for precise replication of the anatomical footprint of the PCL.

LEVEL OF EVIDENCE: IV, prospective case series.