Purpose: A higher posterior tibial slope (PTS) and malpositioning of bone tunnels are known risk factors for anterior cruciate ligament reconstruction (ACL reconstruction; ACLR) failure. However, it remains unclear whether these factors account for the mechanism of failure, whether traumatic or non-traumatic. The purpose of this study was to analyze whether the ACL failure mechanism correlates with a higher PTS or non-anatomical bone tunnels. It was hypothesized that a higher PTS and bone tunnel malposition are associated with non-traumatic ACLR failure. Methods: In this retrospective study, all ACLR failures between 2015 and 2023 treated surgically at a single institution were included. The following factors were evaluated: sex, age at the time of revision surgery, PTS, anatomical versus non-anatomical tunnel placement, concomitant pathologies and fixation techniques. PTS was measured using the Dejour technique. Tibial and femoral tunnels were analyzed according to the method described by Stäubli and Rauschning, and Bernard et al., respectively. A logistic regression analysis was performed to evaluate the effect of each factor on the mechanism of graft failure (traumatic vs. non-traumatic). Results: > 0.05) on the mechanism of ACLR failure. Conclusion: Patients in our cohort with non-traumatic ACLR failure did not demonstrate a higher PTS or a higher incidence of non-anatomically positioned tibial or femoral tunnels compared with patients experiencing traumatic retears. However, non-traumatic cases were associated with a higher prevalence of medial meniscus tears. Level of Evidence: Level III, retrospective comparative study.
Fritsch et al. (Wed,) studied this question.