"Pronation Compensation Sign" as a New Diagnostic Tool for Carpal Tunnel Syndrome: A Prospective Preliminary Study

Carpal tunnel syndrome (CTS) is commonly encountered in clinical practice. Diagnostic tools that currently exist include painful provocative maneuvers, invasive nerve conduction studies and the use of tests that require physician's direct participation in an era of sanitary crisis and virtual consultations. Therefore, having an easily accessible, reliable and practical tool for diagnosing CTS would be highly beneficial. Herein, we investigated the diagnostic value of the "pronation compensation sign" that we described for diagnosing CTS.

We included 18 hands with and 18 hands without CTS (age: CTS hands = 52.5 ± 13.8 years, non-CTS hands = 43.2 ± 12.3 years; sex ratio: CTS hands = 12:8, non-CTS hands = 9:9). The presence of the "pronation compensation sign" was evaluated in each included hand. The presence of the "pronation compensation sign" were compared between CTS and non-CTS hands using the chi-squared test. Statistical significance was set at p < 0.05. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated of the "pronation compensation sign" for CTS.

All 18 hands with CTS showed a positive "pronation compensation sign", while those without CTS were negative. All 18 hands that were positive for the "pronation compensation sign" were hands with CTS, while those that were negative were hands without CTS. The sensitivity and specificity of the "pronation compensation sign" for diagnosing CTS were both 100%. The PPV and NPV of the "pronation compensation sign" for CTS were both 1.000. The rates of the presence of the "pronation compensation sign" were significantly different between hands with and without CTS (p < 0.001).

The "pronation compensation sign" seems a useful tool for diagnosing CTS. We believe that the "pronation compensation sign" will help clinicians diagnose CTS with high diagnostic accuracy.