Jul 14, 2021Revision ACL Failure Increased by Elevated Posterior Tibial Slope
According to at least one orthopaedic sports medicine specialist, an elevated “steep” posterior tibial slope can increase the risk of re-rupturing the graft of patients undergoing ACL reconstruction.
A recent article from Healio.com highlighted the thoughts of Robert A. Duerr, MD, an orthopaedic surgeon at Ohio State University’s Wexner Medical Center. He shared the following statements during a presentation he gave at the American Orthopaedic Society for Sports Medicine and Arthroscopy Association of North American Combined Meeting.
Below is an excerpt from that article on Healio.com.
Duerr and colleagues retrospectively reviewed data from matched cohorts of 38 cases of revision ACL graft failure and 38 control cases with a minimum 2-year follow-up. Researchers used lateral knee radiographs and MRI to assess posterior tibial slope (PTS).
“We know from biomechanical studies that increased tibial slope is associated with increased anterior tibial translation, as well as strain in the ACL,” Duerr said. “There have also been clinical studies that have shown elevated tibial slope both in ACL primary injuries, ACL graft failures and in multiple ACL graft failures.”
He went on to add, “we did five centimeters below the joint line and the lowest visualized portion to define a tibial anatomic axis, and an angle formed at the tangent of the medial and lateral plateaus.”
Researchers noted MRI and radiographic measurements demonstrated “significantly elevated” PTS in the revision failure cohort vs. the control cohort. Radiographic results showed patients with a medial PTS of 14° or more or lateral PTS of 13° or more had an increased risk for revision ACL failure. Additionally, MRI results showed patients with a medial PTS of at least 5° or lateral PTS of at least 6.5° also had an increased risk for graft failure.
Overall, Duerr concluded that patients with radiographic medial PTS of 14° or more had 18.7-times greater odds of revision ACL graft failure compared with the controls.