High-resolution ultrasound in ulnar neuropathy at the elbow: A prospective study.

INTRODUCTION

We examined the role of ultrasound in diagnosing and localizing ulnar neuropathy (UN) at the elbow.

METHODS

Forty-one patients referred for UN and 43 healthy subjects were included. Cross-sectional area (CSA) of the ulnar nerve was measured by ultrasound at 5 locations across the elbow and at the wrist. Patients underwent near-nerve conduction studies (N-NCS).

RESULTS

Ultrasound (US) had a sensitivity of 80.5%, N-NCS had a sensitivity of 70.7%, and combined sensitivity was 85.4% in diagnosing UN. Using N-NCS as a reference standard, US reached a sensitivity of 93.1% and a specificity of 50.0% in diagnosing UN, and a sensitivity of 77.3% and a specificity of 42.9% in localizing UN at the elbow. There was a reduction in mean CSA at 3-month follow-up.

CONCLUSIONS

N-NCS and US are complementary methods and have the potential to increase the sensitivity for diagnosing and localizing UN at the elbow.