Diagnosis of Carpal Tunnel Syndrome in Patients Without Diabetes With Hemodialysis Using Ultrasonography: Is It a Useful Adjunctive Tool?

Objective: (1) To examine the ultrasonography (US) characteristics in patients with hemodialysis-related carpal tunnel syndrome (H-CTS) and (2) to evaluate the accuracy of a proposed US parameter-dynamic ratio of median nerve-to-hamate hook distance (RMHD) in diagnosis of H-CTS. Design: A case-control study. Setting: A tertiary medical center and a secondary hospital from November 2017 to March 2021. Participants: Consecutive patients (N=207) without diabetes under hemodialysis were recruited and divided into a hemodialysis without carpel tunnel syndrome (CTS) (H-Control) group and an H-CTS group. Age-matched volunteers (N=89) without diabetes or upper extremity disorders were enrolled as the control group. Intervention: US examinations by 2 operators blinded to the patient's clinical information. Main Outcome Measures: US parameters including cross-sectional area of the median nerve at the carpal tunnel inlet (CSA-I) and outlet (CSA-O), the flattening ratio of the median nerve at the inlet (FR-I) and outlet (FR-O), and RMHD. Results: Handedness and arteriovenous fistula showed no associations with CSA-I/O and FR-I/O. Compared with the control group (n=69), the CSA-I was significantly larger in the H-Control group (n=63) and H-CTS group (n=76) (P<. 001, both). There were no significant differences in the FR-I/-O among the 3 groups. For the second aim, in the H-CTS group (n=38), there was a significantly lower RMHD compared with both the control (n=20) and H-Control groups (n=30) (0.1%+/- 2.2% vs 3.5 +/- 2.3% and 3.8 +/- 1.7%, P<. 001, both). An RMHD cutoff value of < 2.7% yielded a specificity of 80.0%, a sensitivity of 94.7%, and an overall accuracy of 88.2% in the diagnosis of H-CTS. Conclusions: Neither CSA-I/-O or FR-I/-O have a role in the diagnosis of H-CTS. RMHD might be a useful US parameter in the diagnosis of CTS in patients without diabetes undergoing hemodialysis. (c) 2021 by the American Congress of Rehabilitation Medicine.

Automated summary

This study examines the ultrasonography characteristics in patients with H-CTS and evaluates the accuracy of a proposed US parameter in diagnosing H-CTS. The results indicate that RMHD might be a useful US parameter in diagnosing CTS in patients without diabetes undergoing hemodialysis.