P-NE012. Comparison of orthodromic and antidromic median and ulnar sensory nerve conduction studies in neuropathy

Abstract

Introduction . Median and ulnar nerves are the most frequent nerves involved in the upper limb neuropathy. Sensory nerve conduction studies (NCS) are often practiced to identify the abnormalities in neuropathy. NCS methods consist of orthodromic and antidromic. The antidromic method produces a greater amplitude, faster conduction, yet with the potential of motor nerves stimulation. On the other hand, the orthodromic method shows smaller amplitude, more difficult to detect neuropathy, but do not stimulate motor nerves. Aim: This study compares the orthodromic and antidromic sensory (NCS) examination of median and ulnar nerve using signals in different directions. Methods . A cross sectional study at RSUP dr. Mohammad Hoesin Palembang in the period of July15, 2019 until September15, 2019 was conducted. There were 64 subjects with median and ulnar nerve neuropathies included in the study after selection through inclusion and exclusion criteria. Each sample had an orthodromic and antidromic sensory (NCS) examination. Data analysis used was the kappa comparative hypothesis test. Results . The results of the statistical analysis showed slight agreement with a value of k = 0.01–0.20 between the two orthodromic and antidromic methods in the latency and amplitude of ulnar nerve and latency of median nerve. The kappa result in amplitude of median nerve showed fair agreement with a value of kappa 0.21–0.40, and substantial agreement in velocity with the value of kappa 0.61–0.80. Meanwhile, in ulnar nerve, the velocity showed moderate agreement with the value of kappa 0.41–0.60. Conclusion . Both sensory (NCS) orthodromic and antidromic methods have a good agreement in velocity, thus both methods can be used and are able to provide interpretations of similar abnormalities in neuropathy examination.