Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy. It causes pain and paresthesia in the hand area innervated with median nerve. In 2001, Ahn D-S announced a new method called Hand Elevation Test (HET). In this study, we will investigate the effect of modified hand elevation test (MHET) to increase the pressure of the wrist joint by fully bending both wrists to induce ischemia. This can improve the diagnosis rate through physical examinations of patients with that disease.

We enrolled patients with symptoms of CTS and also showed a reasonable finding of in electrodiagnostic test. We enrolled 63 patients from 2014 to 2017 and exclude 28 patients. Finally, there were 70 hands of 35 patients in experimental group. To doing the HET, patients raised their hands based on their own strength, against gravity above the head. MHET also maintain same position with HET but additionally fully flex wrist joint. All patients enrolled this study were examined electromyography (EMG) exam and sonogram at the wrist and mid forearm level.

In 70 hands enrolled in this study, sensitivity of HET was 75.0% and 77.08% in MHET. Specificity was 68.18% in HET and 63.63% in MHET. Positive predictability was 82.22% and negative predictability was 56% in MHET. Forty-six subjects showed shorter time for inducing positive symptoms in MHET than HET. The group of positive symptoms in MHET showed higher value of the Wrist-Forearm ratio in ultrasonography and larger cross-sectional areas in carpal tunnel inlet in ultrasonography.

In this study MHET showed superior to HET in sensitivity and negative predictability and shortened time to response. Especially, 17 subjects showed reductions in time to response in MHET than HET. So we thought the clinical implication of theses statistical findings is that the MHET may be valid and usable diagnostic method.