01-08-2019 | KNEE
Steep lateral tibial slope and lateral-to-medial slope asymmetry are risk factors for concomitant posterolateral meniscus root tears in anterior cruciate ligament injuries
Published in: Knee Surgery, Sports Traumatology, Arthroscopy | Issue 8/2019
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Purpose
To compare sagittal and coronal tibial slopes between anterior cruciate ligament (ACL) injured subjects with and without posterolateral meniscus root tear (PLRT).
Methods
A chart review was conducted to identify patients with isolated ACL tears and patients with an associated PLRT. Patients with other concomitant injuries and patients who underwent surgery > 6 months after the injury were excluded. Magnetic resonance image data were used to compare the medial and lateral sagittal tibial slope (MTS and LTS), lateral-to-medial slope asymmetry (LTS–MTS), and coronal slope of the tibial plateau between both groups. Mean LTS and standard deviation (SD) of the control group were calculated, and a value of > mean + 1 SD was considered an abnormal LTS. Interobserver reproducibility was assessed by calculating interclass correlation coefficients (ICCs) of measurements independently obtained by two reviewers.
Results
Fifty-nine patients met the in- and exclusion criteria. Thirty nine (66%) had an isolated ACL tear and 20 (34%) had an associated PLRT. Interrater ICCs for LTS, MTS, and coronal slope were 0.930, 0.884 and 0.825, respectively, representing good to excellent interobserver reproducibility. Patients with a PLRT had significantly steeper LTS (8.0 ± 3.2 vs. 4.0 ± 2.0; p < 0.001) and significantly greater difference of LTS–MTS (3.7 ± 2.9 vs. − 0.6 ± 2.0; p < 0.001). Furthermore, patients with abnormal LTS were significantly overrepresented among patients with PLRT (70% vs. 18%; p < 0.001). No significant difference between both groups was found for MTS and coronal slope.
Conclusion
A steep lateral tibial slope and lateral-to-medial slope asymmetry are risk factors for concomitant PLRT in ACL-injured subjects.
Level of evidence
IV, retrospective cohort study.