Effect of "normal" versus "mild carpal tunnel syndrome" electrodiagnostic report on surgeon decision and patients clinical outcomes

Introduction: There exist conflicting electrodiagnostic reports between diagnosing mild carpal tunnel syndrome (CTS) and normal results, depending on the interpretation methods used by electrodiagnosticians. This underscores the necessity for precise clinical guidelines. This study aims to assess how the variation between mild and normal electrophysiological reports impacts (1) subsequent clinical outcomes in patients diagnosed with CTS and (2) physicians' decision-making.

Methods: In a prospective cohort study, we followed 102 patients with suspected CTS who underwent electrodiagnostic studies (EDX). The EDX results for these patients were categorized as either normal or indicative of mild CTS, based on the interpreter's chosen assessment method, which included median-ulnar palmar mixed comparison or median sensory nerve studies. Patient demographics, EDX reports, the choice between surgical or non-surgical treatment, as well as repeated measurements of post-operative pain and paresthesia, were collected at day 0, two weeks, and 12 weeks post treatment.

Results: The study includes an equal number of patients with mild and normal electrodiagnostic reports, totaling 51 individuals in each group, and revealed no significant differences in their demographic and baseline characteristics. Over time, both groups showed a decrease in symptom severity. Nevertheless, the reduction in pain (P = 0.77 at 12 weeks) and paresthesia (P = 0.32 at 12 weeks) showed no significant differences between the two groups. Furthermore, there were no differences observed between the groups concerning the treatment choices made by the surgeon (P = 0.218).

Conclusion: When EDX reports indicate either normal or mild CTS, it seems that this interpretation doesn't substantially influence a surgeon's decision in selecting the treatment option or the resulting clinical outcome post-treatment. This highlights the importance of clinical assessment rather than relying solely on EDX reports in managing these patients.

Level of evidence: Level II (Prospective cohort study).