Clinical neurophysiology : official journal of the International Federation of Clinical Neurophysiology

Diagnostic accuracy of ultrasonographic and nerve conduction studies in ulnar neuropathy at the elbow.

PMID 25541522


To report diagnostic accuracy of ultrasonography (US) and compare it to standard 10-cm nerve conduction studies (NCSs), and short-segment NCSs (SSNCSs) across the elbow in the diagnosis of ulnar neuropathy at the elbow (UNE). In a broad spectrum of consecutive patients with suspected UNE a prospective and blinded study was performed. This included a clinical examination, electrodiagnostic (EDx) and US studies. In clinically definite UNE patients we compared the sensitivity of SSNCSs, of 10-cm NCSs across the elbow, and of US. The specificity was calculated in asymptomatic controls. We studied 113 affected arms in 109 patients; definite UNE was diagnosed in 81, and alternative conditions in 12 arms. The sensitivity of SSNCSs was 89%, of 10-cm NCSs 83%, and of US 71%. We found the highest sensitivity of US in patients with axonal UNE (93%), followed by conduction slowing (82%) and conduction block (55%). Specificity of SSNCSs was 80%, of 10-cm NCSs 82%, and of US 82%. The present study found the highest diagnostic accuracy of SSNCSs (85%), followed by 10-cm NCSs (83%), and of US (77%). US is particularly useful in patients with axonal UNE, while SSNCSs in UNE with conduction block.