Electrodiagnostic Testing in the Diagnosis and Management of Carpal Tunnel Syndrome.

and Management of Carpal Tunnel Syndrome To the Editor: The May/June guest editorial1 raised several issues regarding the use of electrodiagnostic testing in the diagnosis and management of carpal tunnel syndrome. In this guest editorial, Dr Fowler expressed concerns regarding the sensitivity and specificity of electrodiagnostic testing in carpal tunnel syndrome, the benefit of confirmatory electrodiagnostic testing, and the financial irresponsibility of such testing. However, Dr Fowler failed to take into consideration current literature and overlooked some of the benefits of confirmatory electrodiagnostic testing in carpal tunnel syndrome. Recent efforts to optimize electrodiagnostic testing in carpal tunnel syndrome have yielded techniques including novel motor comparison studies, which have a diagnostic sensitivity and specificity of 93% and 97%, respectively.2 Zis et al3 also recently described a motor comparison technique with a diagnostic sensitivity of 91% and a specificity of 93%. These methods for diagnosing carpal tunnel syndrome significantly outperform those referenced in the guest editorial. Dr Fowler’s own research, using traditional nerve conduction study techniques, revealed a better diagnostic sensitivity and specificity than those reported in the references chosen for the guest editorial.4 These articles reveal that the sensitivity and specificity of electrodiagnostic studies in carpal tunnel syndrome are actually much higher than reported in the guest editorial. In contrast to Dr Fowler’s claim, there are data suggesting that electrodiagnostic testing can provide some information regarding prognosis after surgery. In fact, Dr Fowler has published on the role of preoperative electrodiagnostic testing in predicting symptom recovery after carpal tunnel surgery, concluding that severity on preoperative nerve conduction studies predicted the rate of postoperative symptom resolution.5 This contradicts the guest editorial and highlights some of the additional information provided by confirmatory electrodiagnostic testing in carpal tunnel syndrome. In the guest editorial, Dr Fowler addresses the financial component of electrodiagnostic testing in carpal tunnel syndrome by stating that, “Numerous physicians have a large financial incentive to perform confirmatory electrodiagnostic testing.” However, since 2013, Centers for Medicare & Medicaid Services reimbursement for electrodiagnostic testing has been cut by more than 50% on average, minimizing the “financial incentive” for confirmatory electrodiagnostic testing. Conversely, according to the Centers for Medicare & Medicaid Services physician fee schedule, the national average for an open carpal tunnel release is nearly double that of a standard electrodiagnostic test for carpal tunnel syndrome.6 Anesthesia and facility fees further increase the surgical cost. One could make the argument that the elimination of confirmatory electrodiagnostic testing could lead to an increase in carpal tunnel release surgery. Perhaps the presence of confirmatory electrodiagnostic testing ultimately minimizes health care–associated costs in carpal tunnel syndrome management. In this era of unprecedented medical advances, it is important to appreciate that established does not equal outdated or wrong. The literature regarding electrodiagnostic testing in carpal tunnel syndrome is sizeable. An analysis of the current literature supports the diagnostic utility and highlights the benefits of confirmatory electrodiagnostic testing in carpal tunnel syndrome. Marcus J. Magnussen, DO Indianapolis, Indiana John Morren, MD Cleveland, Ohio The authors have no relevant financial relationships to disclose.