Diagnostic accuracy of ultrasound for detecting posterior ligamentous complex injuries of the thoracic and lumbar spine: A systematic review and meta-analysis

Background: Posterior ligamentous complex injuries of the thoracolumbar (TL) spine represent a major consideration during surgical decision-making. However, X-ray and computed tomography imaging often does not identify those injuries and sometimes magnetic resonance imaging (MRI) is not available or is contraindicated. Objective: To determine the diagnostic accuracy of the ultrasound for detecting posterior ligamentous complex injuries in the TL spine. Materials and Methods: A systematic review was carried out through four international databases and proceedings of scientific meetings. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and their 95% confidence intervals (CIs) were estimated, by using weighted averages according to the sample size of each study. Summary receiver operating characteristic was also estimated. Results: A total of four articles were included in the meta-analysis, yielding a summary estimate: Sensitivity, 0.89 (95% CI, 0.86-0.92); specificity, 1.00 (95% CI, 0.98-1.00); positive likelihood ratio, 224.49 (95% CI, 30.43-1656.26); negative likelihood ratio, 0.11 (95% CI, 0.05-0.19); and diagnostic odds ratio, 2,268.13 (95% CI, 265.84-19,351.24). There was no statistically significant heterogeneity among results of included studies. Summary: Receiver operating characteristic (±standard error) was 0.928 ± 0.047. Conclusion and Recommendation: The present meta-analysis showed that ultrasound has a high accuracy for diagnosing posterior ligamentous complex injuries in patients with flexion distraction, compression, or burst TL fractures. On the basis of present results, ultrasound may be considered as a useful alternative when magnetic resonance imaging (MRI) is unavailable or contraindicated, or when its results are inconclusive.