Influence of Shoulder External Rotation Component on Median Nerve Neurodynamics in Neurogenic Cervicobrachial Pain Syndrome: A Cross-Sectional Study

Abstract

Background. The upper limb neural tissue provocation test-1 (ULNTPT-1) is used for determining the neurogenic etiology of neck and arm pain. Biomechanical studies have primarily investigated in vitro, whereas in vivo examination is lacking. Objective. The objective was to determine the effect of the shoulder external rotation (ER) component of ULNTPT-1 on the deficit in elbow extension range of motion (EEROM) and vibration threshold (VT) in participants with neurogenic cervicobra-chial pain syndrome (CBPS). Methods. Thirty-two patients were included in the study as per the inclusion criteria. ULNTPT-1 with/without shoulder external rotation was performed on symptomatic and asymptomatic side. Deficit in EEROM at the onset of muscle activation of biceps brachii (R1) and initial onset of pain (P1) along with VT in median nerve territory was recorded. One-way ANOVA was used to compare the difference and level of significance was p < 0.05. Results. The effect of ULNTPT-1 with/without shoulder ER component on the deficit in EEROM at P1 & R1 was significant on symptomatic as well as on the asymptom-atic side (p < 0.001). The difference was not significant on symptomatic (p = 0.15) and asymptomatic sides (p = 0.31) for the VT. The difference in value of responses obtained on each side with/without shoulder ER compared, showed no significant difference in all three outcomes P1, R1, and VT (p = 0.219; p = 0.273; p = 0.145). Conclusions. There was greater deficit in EEROM with shoulder ER, which suggest that there is a heightened nerve mechanosensitivity with shoulder ER component of ULNTPT-1. Study registration. Clinical Trial Registry India received a prospective registration for the trial with the number CTRI/2018/04/013383.