Purpose We report three patients with a rare variant of Duane's retraction syndrome. Methods Eye movements were recorded by electro- oculography. One patient underwent electromyography. Results All patients showed V-incomitance and twitch abduction on vertical saccades. Electromyography showed lateral rectus muscle firing activity during upgaze and downgaze. Conclusion Our patients showed synergistic innervation between the lateral rectus muscle and ipsilateral vertical acting muscles documented by electromyography.