Validity of high-resolution ultrasonographic measurement versus electrophysiological study in the detection of frequency of carpal tunnel syndrome in patients with rheumatoid arthritis

Abstract EN

Objectives : This study aimed to determine the frequency of occurrence of carpal tunnel syndrome (CTS) in rheumatoid arthritis (RA) patients, determine its relation to disease activity, describe the ultrasonographic (US) finding of CTS, and compare the diagnostic value of US with the electrodiagnosis in the detection of CTS.

Patients and methods : This study was carried out on 54 adult RA patients (group II) compared with 20 healthy volunteers as controls (group I).

The disease activity in all patients was assessed using DAS28.

All patients and controls underwent complete rheumatological and neurological examinations.

Nerve conduction study (NCS) and high-resolution sonography were assessed in a blinded manner to clinical data.

The patients were subdivided into two groups according to the measurement of NCS (group IIA : RA patients with CTS and group IIB : RA patients without CTS).

Results : The frequency of CTS in RA patients was 40.7 %.

A strong positive correlation was found between group IIA and the disease activity scale (P < 0.0001).

There was a significantly higher level of cross-sectional area at the carpal tunnel inlet in group IIA than in group IIB and the control group (P < 0.0001).

There was a significant correlation between the mean cross-sectional area with the grades of CTS detected by the electrophysiological study.

The area under the curve was large for all receiver operating characteristic curves for each measurement (0.800).

Conclusion : The frequency of CTS in RA patents is high.

High-frequency US examination of the median nerve should be strongly considered as a new alternative diagnostic modality for the evaluation of CTS.

Sonography is probably preferable because it is painless, fast, easily accessible, and preferred by the patients.