Developing Normative Reference Values for Nerve Conduction Studies of Commonly Tested Nerves among a Sample Pakistani Population

Abstract

Introduction: Most neurophysiology departments around the world establish their own normative data. However, ethnic differences are not taken into account. Our aim was to establish normal nerve conduction studies (NCS) data for routinely tested nerves in individuals of Pakistani (South Asian) origin and to compare with Western published data.

Materials and methods: One hundred healthy adults' nerves were assessed, using standardized techniques. Individuals were grouped into age groups. Gender differences were assessed.

Results: Of the 100 volunteers, 49 were female and 51 were male. Their mean age was 39.8 years. Findings showed statistically significant prolongation of median distal motor latency (DML) and F-wave latency with age and reduction of median, ulnar, and sural sensory amplitudes as age increased. Gender differences showed consistent difference in the normal values for median, ulnar, and peroneal DMLs and respective F-wave latencies, which were significantly shorter in females. Sensory amplitudes of tested upper extremity nerves were significantly lower in males. Comparing with available data, our findings are similar to the Saudi population but significantly different from the American and multiethnic Malaysian populations. Pakistani individuals generally have significantly higher amplitudes and faster conduction velocities with similarities to South Asian studies.

Conclusions: We recommend normative NCS parameters for commonly tested nerves for the Pakistani population, using standardized techniques to ensure highest quality testing and outcomes.

Keywords: Nerve conduction studies; normal values; normative data; practices standards; reference values.