Ultrasonographic Evaluation of Ulnar Neuropathy Around the Elbow in Diabetes Mellitus

Abstract

Objective: We evaluated the usefulness of ultrasonography for subclinical ulnar neuropathy at the elbow (UNE) in patients with diabetes.Methods: Ultrasonography of the ulnar nerve was performed on 140 limbs in 73 patients with diabetes mellitus at 8 standardized sites proximal and distal to the medial epicondyle (1-cm intervals). The ulnar nerve cross-sectional area (CSA) at each site was analysed according to the presence of electrophysiological diabetic polyneuropathy (DPN) or UNE (UNE_e).Results: Fifty-nine limbs were electrophysiologically normal, 22 limbs had UNE, 39 limbs had DPN, and 20 limbs had DPN and UNE_e. In patients without DPN, the maximal CSA, swelling ratio, and CSAs were greater in the UNE_e group than in the normal group (p < 0.01). No significant differences were noted between the DPN and DPN+UNE_e groups regarding the CSAs, maximal CSA, and swelling ratio.Conclusion: Ultrasonography of ulnar nerve swelling is helpful for diagnosing subclinical UNE in patients with diabetes.