Validity of the lever sign test for the clinical diagnosis of anterior cruciate ligament tears: Assessments in ski resorts

Lever sign test shows high diagnostic accuracy for anterior cruciate ligament injuries: A systematic review and meta-analysis of 3299 observations

PURPOSE

Injuries of the anterior cruciate ligament (ACL) are common knee injuries among active and younger patients. The Lever Sign Test (LST) is a relatively newer test, of which the accuracy is disputed in the existing literature. The aim of this study was to assess the accuracy with and without anesthesia of the Lever Sign test in the literature.

METHODS

PRISMA guidelines were followed, studies were identified using PubMed, EMBASE and Google Scholar. All studies that reported accuracy of LST performed by a clinical professional were included. Integrity of ACL was confirmed using magnetic resonance imaging or arthroscopy. Sensitivity and specificity were calculated using uni- and bivariate methods.

RESULTS

After inclusion, 3299 observations in 2516 patients were included from 23 studies. Mean age was 31.8 years and 64.2% were male. Without anesthesia, sensitivity was 79.2% (95% CI 68.7-86.9) and specificity was 92.0% (95% CI 82.2-96.6). An area under the curve (AUC) of 86.1% was found. With anesthesia, sensitivity was 86.6% (95% CI 68.0-95.2), specificity was 93.4% (95% CI 84.5-97.3) and the AUC was 91.6%.

CONCLUSION

The Lever Sign test shows very good to excellent accuracy for ACL injury, and is a useful tool for clinical practice.

Lever sign test for anterior cruciate ligament injuries: a diagnostic meta-analysis

BACKGROUND

Sports-related ACL (anterior cruciate ligament) injuries are frequent. Successful management requires early diagnosis and treatment. One of the clinical tests used to identify ACL damage is the lever sign test. This meta-analysis aimed to assess the lever sign test's diagnostic efficacy for ACL injuries.

METHODS

An extensive investigation of the Cochrane Library, Embase, and PubMed databases was conducted until April 2023. Studies assessing the lever sign test's diagnostic efficacy for ACL injuries were also included. A bivariate random-effects model was employed to acquire the pooled estimates of diagnostic odds ratios, specificity, positive and negative likelihood ratios, sensitivity, and curves of the summary receiver operating characteristic (SROC).

RESULTS

The meta-analysis comprised twelve investigations with a total of 1365 individuals. The lever sign test's combined sensitivity and specificity for the purpose of diagnosing injuries to the ACL were 0.810 (95% confidence interval [CI] 0.686-0.893) and 0.784 (95% CI 0.583-0.904), respectively. The positive and negative likelihood ratios were 3.148 (95% CI 1.784-5.553) and 0.210 (95% CI 0.084-0.528), respectively. The study revealed a diagnostic odds ratio of 17.656, with a 95% CI ranging from 4.800 to 64.951. The SROC curve's area was determined to be 0.912 (95% CI 0.857-0.967).

CONCLUSION

With high specificity and sensitivity, the lever sign test is a reliable diagnostic modality for ACL injuries. However, the test should be used in combination with other diagnostic tests to increase the accuracy of the diagnosis. Further investigations are warranted to assess the clinical practicability of the lever sign test in various populations and settings.

Lateral femoral chondral lesions are more frequent when an anterior cruciate ligament tear is concomitant with a lateral femoral notch sign, but do not progress over time

BACKGROUND

The lateral femoral notch sign (LFNS) is caused by an impact to the lateral femoral condyle during a pivot shift injury and affects 25% to 33% of patients with an anterior cruciate ligament (ACL) rupture. The primary aim of this study was to compare the incidence of chondral lesions 1year after ACL reconstruction, while taking into consideration preoperative chondral damage, in patients with and without a preoperative LFNS. The primary outcome measure was the presence of chondral lesions involving the lateral femoral condyle, confirmed on magnetic resonance imaging (MRI) using the Outerbridge classification, at 1year postoperative. The secondary outcome measures were bone bruise of the lateral femoral condyle confirmed on MRI, the International Knee Documentation Committee (IKDC), Lysholm and Tegner functional scores taken 1year after surgery.

METHODS

Sixty patients were included-30 with preoperative LFNS and 30 without-in a retrospective, comparative study of prospectively collected data on patients operated between August 2018 and December 2020.

RESULTS

A lateral femoral chondral lesion 1year after surgery was significantly more common in the group with a preoperative LFNS (37% [n=11] versus 13% [n=4] in the group without a preoperative LFNS, p=0.036). Adjusting the statistical analysis for preoperative body mass index (BMI) did not impact these results (adjusted odds ratio [OR]=3.83 [95%CI: 1.03-14.24]; p=0.045). Adjusting for a preoperative lateral femoral chondral lesion had an impact on these results (adjusted OR=0.78 [95%CI: 0.12-5.08]; p=0.793). This indicates that a preoperative LFNS is not significantly and independently associated with a lateral femoral chondral lesion at 1year postoperative when the analysis is adjusted for a preoperative lateral femoral chondral lesion. However, having a preoperative lateral femoral chondral lesion is significantly correlated with the presence of a lateral femoral chondral lesion 1year after the surgery (adjusted OR=63.31 [95%CI: 5.94-674.8]; p=0.001). There were no significant differences in terms of bone bruise on MRI (p=1.0), or for the IKDC (p=0.310), Lysholm (p=0.416) and Tegner (p=0.644) functional scores. The LFNS was still present in 21 out of 30 patients (70%) at 1year postoperative. The preoperative LFNS was significantly smaller in the group without a chondral lesion compared to the group with a chondral lesion 1year after the surgery (median=2.30mm [IQR: 1.40; 3.00] versus 3.10mm [IQR: 2.50; 3.40]; p value=0.045).

CONCLUSIONS

Patients with a preoperative LFNS are three times more likely to have a chondral lesion in the notch region 1year after surgery. These chondral lesions are concomitant to the injury and do not progress over time.

LEVEL OF EVIDENCE

III.