Purpose: The objective of this investigation was to evaluate the precision of tibial tunnel drilling for anatomic anchoring of meniscus transplants at the tibial insertion area, using previously obtained percentage references.

Methods: In 20 cadaveric tibial heads, anterior and posterior horn insertions of both the lateral and the medial meniscus were dissected and their circumferences outlined. Standardized photographs of the tibial plateau were obtained. Applying previously obtained percentage values for radiographic determination of the meniscus insertion midpoints, tibial tunnels were drilled with the use of a standard ACL-guide. The positioning of the drilling guide was performed by solely using the midpoints as determined on standard ap and lateral radiographs; during the procedure, no position correction related to the anatomic insertions was made. After tibial tunnel drilling, a second set of standardized photographs of the tibial plateau was obtained. Adobe Photo Shop permitted the superposition of pre- and postoperative images. Coincidence between the anatomic insertion areas and the footprint of the tibial tunnel exit was determined, as well as the distance between the borders of the insertion areas and the tunnel footprint.

Results: For the lateral meniscus, the mean coincidence of insertion area and tunnel footprint was 60.5 ± 34.6 % for the anterior horn insertion and 62.4 ± 32.0 % for the posterior horn insertion. The mean distance between the borders of insertion area and tunnel footprint was 1.7 ± 1.5 mm for the anterior horn insertion and 2.3 ± 1.7 mm for the posterior horn insertion.

For the medial meniscus, the mean coincidence of insertion area and tunnel footprint was 88.4 ± 15.5 % for the anterior horn insertion and 60.3 ± 31.6 % for the posterior horn insertion. The mean distance between the borders of insertion area and tunnel footprint was 0.8 ± 0.8 mm for the anterior horn insertion and 2.1 ± 1.4 mm for the posterior horn insertion.

Conclusions: The use of percentage references for tibial meniscus insertion midpoint determination in combination with a radiographic positioned standard ACL-guide permits a precise drilling of tibial tunnels at the anatomic location of the meniscus insertions.

Clinical relevance: Enhancement of the surgical technique for bone plug fixation of lateral and medial meniscus transplants.