Point-of-care ultrasound: a viable alternative for assessing ulnar neuropathy in rheumatoid arthritis?

This study seeks to evaluate the effectiveness of ultrasound measurements of the ulnar nerve cross-sectional area in comparison to electrodiagnostic tests for identifying ulnar nerve entrapment at the elbow in rheumatoid arthritis.

This study was designed as a cross-sectional observational analysis involving 90 individuals, divided into three groups: Group A consisted of 30 individuals diagnosed with rheumatoid arthritis without clinical signs of ulnar neuropathy at the elbow; Group B included 30 individuals with rheumatoid arthritis exhibiting clinical indicators of ulnar neuropathy at the elbow; and Group C comprised 30 healthy controls. Each participant underwent a thorough medical history assessment, along with both clinical and neurological evaluations. Additionally, ultrasound and electrophysiological assessments of the ulnar nerve were performed.

There was no significant demographic difference between the groups, except for age, which was notably lower in Group A compared to Group B. Additionally, abnormalities in nerve conduction studies and cross-sectional area were found to be significantly greater in Group B (p <0.0001). The cross-sectional area demonstrated diagnostic accuracy rates of 52.22%, 62.22%, and 78.89% for identifying ulnar neuropathy at Guyon's canal, the medial epicondyle, and based on the elbow-to-wrist ratio, respectively.

Ultrasonography exhibits high diagnostic accuracy, especially with the cross-sectional area at the medial epicondyle and the elbow-to-wrist cross-sectional area ratio serving as important indicators for ulnar nerve entrapment in patients with rheumatoid arthritis.