Assessment of carpal tunnel syndrome: Overview of clinical tests

Study design. Narrative review of diagnostic studies. Introduction. Carpal tunnel syndrome (CTS) is one of the most common pathologies of the peripheral nervous system. Several clinical tests have been proposed to diagnose CTS, despite the fact that their psychometric properties continue to be disputed. The aim of this contribution is to collect, through a narrative review of literature, scientific evidence on the accuracy (reliability and validity) of diagnostic tests in CTS, and summarize current knowledge. Methods. Research was carried out in the main biomedical electronic databases (PubMed, PEDro, EMBASE, CINAHL, Cochrane Library). The following key words were used: “Carpal tunnel syndrome”, “Physical examination”, “Nerve conduction testing”, “Median neuropathy”, “Tension test”, “Diagnostic testing”, with no limits of date and in English, Spanish, Portuguese, French and Italian. Results. This review concerns the following assessment tools: the Hand Diagram, the Inspection, the Neurological Exam, Tinel's test, Phalen's and Phalen's reverse tests, the Pressure Provocation Tests, the Upper Limb Neurodynamic Tests, and clusters of tests. Other tests such as the Tethered Median Nerve Stress test, the Hand elevation test, the Flick sign, the Closed Fist Sign, and the Tourniquet test are less used in clinical practice. The rates of reliability and diagnostic accuracy of various tests commonly used in CTS appear conflicting. Conclusion. To make the correct diagnosis, it is advisable to use a cluster of tests rather than a single test. The development of "clinical prediction rules" may be one of the most interesting perspectives for the diagnosis of CTS.