Posterior lateral meniscal root tear due to a malpositioned double-bundle anterior cruciate ligament reconstruction tibial tunnel.

UNLABELLED: The posterior lateral (PL) meniscal root plays an essential role in ensuring the health of the articular cartilage of the knee joint. Injuring the PL meniscal root has been demonstrated to result in significant deleterious changes to tibiofemoral contact mechanics. Anatomic studies have reported that the posterolateral bundle of the anterior cruciate ligament (ACL) and PL root lie in close proximity on the tibial plateau. Therefore, during a double-bundle ACL reconstruction, the PL root may be inadvertently injured during the reaming of the posterior ACL double-bundle reconstruction tibial tunnel that is intended to recreate the posterolateral bundle of the ACL. This case report describes an occurrence of iatrogenic injury to the PL root due to a posteriorly malpositioned double-bundle ACL tibial tunnel. This report is the first known description of this mechanism of injury in the literature. LEVEL OF EVIDENCE: Case report, Level IV.