The presence of a deep lateral femoral notch sign in ACL-injured patients is associated with a 2.7° steeper posterior tibial slope and a 19% higher frequency of lateral meniscal injuries

José N P da Silva Vilhena Braz; Luís F T G Alves; Fábio A L Ferreira; António S Barros; António M S N de Sousa; Manuel A P Gutierres

doi:10.1002/ksa.12262

The presence of a deep lateral femoral notch sign in ACL-injured patients is associated with a 2.7° steeper posterior tibial slope and a 19% higher frequency of lateral meniscal injuries

Knee Surg Sports Traumatol Arthrosc. 2024 May 15. doi: 10.1002/ksa.12262. Online ahead of print.

Authors

José N P da Silva Vilhena Braz¹, Luís F T G Alves², Fábio A L Ferreira³, António S Barros⁴, António M S N de Sousa^{1

2}, Manuel A P Gutierres^{1

2}

Affiliations

¹ Faculty of Medicine, University of Porto, Porto, Portugal.
² Department of Orthopaedics and Traumatology, São João University Hospital, Porto, Portugal.
³ Department of Radiology, São João University Hospital, Porto, Portugal.
⁴ RISE - Department of Physiology and Surgery, Faculty of Medicine, University of Porto, Porto, Portugal.

PMID: 38751091
DOI: 10.1002/ksa.12262

Abstract

Purpose: The purpose of this study was to study the relationship between the presence of a deep lateral femoral notch sign (DLFNS) in anterior cruciate ligament (ACL)-injured patients and a higher posterior lateral tibial slope (LPTS), a reduced meniscal bone angle (MBA), a higher LPTS/MBA ratio and a higher incidence of concomitant injuries in primary ACL tears.

Methods: A retrospective case-control study was performed in patients submitted to primary ACL reconstruction with an available preoperative magnetic resonance imaging (MRI) scan. Patients with ACL tears and a femoral impactation with a depth ≥2 mm were assorted to the DLFNS group and patients with ACL tear and without a DLFNS to the control group. LPTS and MBA were measured in MRI. The presence of concomitant injuries (meniscal, posterior cruciate ligament, medial collateral ligament, lateral collateral ligament and bone injuries) was assessed in MRI. Quantitative data are presented in the median ± interquartile range (IQR).

Results: There were 206 patients included in the study, with 46 patients assorted to the DLFNS group and 160 patients to the control group. In the DLFNS group, the median LPTS was 6.7° (IQR: 4.0-8.2) versus 4.0° in the control group (IQR: 2.2-6.5) (p = 0.003). The LPTS/MBA ratio was significantly higher in the DLFNS group, with a median of 0.32 (IQR: 0.19-0.44), in comparison to the control group, with a median of 0.19 (IQR: 0.11-0.31) (p < 0.001). The multivariable logistic regression analysis showed that the LPTS is an independent risk factor to having a DLFNS (odds ratio [OR] = 1.161; 95% confidence interval [CI]: 1.042-1.293, p = 0.007). There was a higher incidence of concomitant lateral meniscal injuries in the DLFNS group (67% vs. 48%, p = 0.017).

Conclusions: In patients with ACL tears, the presence of a DLFNS is associated with a steeper lateral posterior tibial slope, as well as a higher incidence of concomitant lateral meniscal injuries.

Level of evidence: Level III.

Keywords: anterior cruciate ligament; biomechanics; femur head; knee injuries; tibial meniscus injuries.

Grants and funding

None