Ultrasonographic Evaluation of Ulnar Neuropathy at the Elbow: A Systematic Review and Meta-Analysis

Several studies have aimed to discuss the Ultrasonographic (US) findings in the assessment of ulnar neuropathy at elbow; however, the current data are widely heterogeneous and it seems necessary to summarize the original studies to reach a consensus. The goal of this study was to conduct a systematic review on the ultrasound measurements of ulnar nerve cross-sectional area at the elbow among patients with definite diagnosis of ulnar neuropathy.

The global databases including Medline, Web of Science, Cochrane Library, Google Scholar, and Scopus were deeply evaluated for all eligible English studies. Among the 343 initially retrieved articles, 31 studies met the eligibility criteria and were published from 2000 April to 2019 December. After excluding the non-eligible articles, 18 manuscripts were systematically reviewed with the goal of assessing Cross-Sectional Area (CSA) at different levels regarding the elbow using different techniques and by various types of transducer ranged from 4-18 MHZ. Data extraction was independently performed by two reviewers on some structured data-collection forms.

The summary of following details were systematically reviewed for the included studies: technique of US measurement and type of transducer, as well as cut-off value and diagnostic capability of the ultrasonography. The collected data were analyzed in STATA software using random or fixed-effect models, as effect size measures such as raw or standardized mean differences (MD or SMD).

In the current meta-analysis, it was proved that ultrasound could be a suitable device to diagnose ulnar neuropathy at elbow, with acceptable sensitivity (72.0-76.1%) and specificity (76.1-81.8%) values.