ULNT2 – Median Nerve Bias: Examiner Reliability and Sensory Responses in Asymptomatic Subjects

Abstract

Interpreting patients' responses to any neurodynamic test requires knowledge of test reliability and of the sensations provoked in asymptomatic subjects. The purpose of our study was to determine examiner reliability for using a standard goniometer to measure shoulder abduction at end-range of a modified brachial plexus tension test commonly known as upper limb neurodynamic test 2 – median nerve bias (ULNT2 – median nerve bias). Our test-retest design on 21 asymptomatic subjects revealed “good” to “excellent” intra-tester reliability with intraclass correlation coefficients (ICC 3, k) of 0.88 and 0.94 for the two examiners. Corresponding standard errors of measurement (SEM) were 2.41 and 2.08 degrees. Inter-tester reliability was “poor” (ICC 2, k = 0.33, SEM = 6.35). Sensory responses provoked in the end position of this neurodynamic test were most commonly located in the lateral hand, lateral forearm, and cubital fossa, areas consistent with the cutaneous distribution of the C6 and C7 dermatomes and median nerve. Pulling was the most common description of sensations experienced in the cubital fossa and forearm, while combinations of pulling, burning, or tingling were more often reported in the hand. Contralateral cervical sidebending increased upper limb sensory responses in all subjects. These sensory responses are consistent with previous reports on ULNT2 – median nerve bias and the original brachial plexus tension test. Further studies are necessary to determine whether our results can assist in establishing the clinical validity and diagnostic performance of this neurodynamic test in symptomatic populations.