Anatomic all-epiphysial tibial tunnels for anterior cruciate ligament reconstruction in skeletally immature knees may be placed without damaging the anterior meniscus root. Issue 1 (8th January 2018) - Shea, Kevin G
Abstract : Objectives: The purpose of this study was to evaluate the spatial relationship of the anterior horns of the menisci and the tibial tunnel during all-epiphysial drilling of skeletally immature specimens and identify any iatrogenic damage or destabilisation to the meniscus and meniscal root. Methods: Four skeletally immature cadaveric knee specimens (aged 9–11 years) were used to create three-dimensional models from CT images. All-epiphysial anterior cruciate ligament (ACL) tibial tunnel drilling was performed in 14 specimens (aged 7–11 years), entering the joint surface at the ACL footprint and avoided the proximal tibial physis. The anterior meniscal roots and horns were closely inspected visually and probed for stability, prior to drilling. After drilling, the meniscus and attachment points were re-evaluated for damage to the meniscus, meniscus root and probed to evaluate for destabilisation. Results: All-epiphysial tunnels entered the joint at the anatomic ACL tibial footprint. Direct visual inspection of the menisci demonstrated an absence of damage to either meniscus or anterior horn regions in all specimens. Probing and traction of the medial and lateral meniscal tissue did not demonstrate evidence of instability or destabilisation of the anterior horn or meniscus root before or after drilling. All tunnels were circumferentially intact at the joint surface, with no evidence of superior tunnel perforation due to shallow tunnel angle. Conclusion: In this study, tunnel placement did not produce damage to either meniscus, nor noticeably destabilise the meniscal roots. This study also demonstrated that drill holes can be placed within the ACL footprint without entering the joint on the proximal tibia surface anterior to the ACL attachment, although the 'safe zone' for drill hole placement is limited. All-epiphysial ACL tibial tunnels can create a large aperture at the tibial joint surface, but these tunnels can be placed at the anatomic footprint of the ACL, without causing gross anterior medial or lateral meniscus horn or root injury.