Journal of the Neurological Sciences 352 (2015) 107 Contents lists available at ScienceDirect Journal of the Neurological Sciences journal homepage: www.elsevier.com/locate/jns Letter to the Editor Appendicular ataxia without position sense loss in a patient with parietal lobe infarct Keywords: Ataxia Position sense Parietal lobe Infarct A 86-year-old lady presented with sudden onset of appendicular ataxia of the right arm with minimal weakness and no deep sensory loss. On neurological exam, she had minimal pronator drift. She had undershooting and overshooting on attempting to reach the target finger on finger to nose test. She also has dysdiadokokinesia and uncontrolled rebound. The tests were not worsened with eyes closed. The sensory exam was unremarkable including normal proprioception. Her brain MRI showed an area of acute infarct in left posterior parietal lobe (Fig. 1) and no other lesion. Although parietal ataxia is generally considered to result from loss of proprioceptive feedback inputs to the motor function [1], but our patient showed clinical features of classic cerebellar kinetic ataxia without loss of proprioception. Brain MRI showed involvement of superior and part of inferior parietal lobules with preserving paracentral lobule which is presumably responsible for sensory innervation of contralateral limbs. This unique clinical scenario might direct toward a strategic spot for ataxia independent of loss of position sense in the parietal lobe. In primates, the counterpart of area 5 of humans is the main parietal area to project to the ventrolateral nucleus of the thalamus, in the exact same location which receives fibers from the cerebellum [1,2]. This area primarily occupies the superior parietal lobule and is separated from the primary and complex proprioceptive projection areas and could account for the cerebellar ataxia without loss of proprioception presented by our patient. Conflict of interest The Authors have no conflict of interest. Disclosure The authors have nothing to report. Study funding No funding to report. References [1] Ghika J, Bogousslavsky J, Uske A, Regli F. Parietal kinetic ataxia without proprioceptive deficit. J Neurol Neurosurg Psychiatry 1995;59:531–3. [2] Wiesendanger R, Wiesendanger M, Rüegg DG. An anatomical investigation of the corticopontaine projection in the primate (Macaca fascicularis and Saimiri sciureus)—II. The projection from frontal and parental association areas. Neuroscience 1979;4(6): 747–65. Ashkan Mowla Stroke Program, Department of Neurology, State University of New York at Buffalo, 100 High Street, Buffalo, NY 14202, United States Corresponding author. E-mail address: mowla_a@yahoo.com. Haris Kamal Stroke Program, Department of Neurology, State University of New York at Buffalo, 100 High Street, Buffalo, NY 14202, United States S. Ali Nabavizadeh Department of Radiology, Hospital of the University of Pennsylvania, Philadelphia, PA, United States 3 March 2015 Fig. 1. Brain MRI diffusion weighted image shows diffusion restriction in the left posterior parietal lobe consistent with acute to subacute infarct. http://dx.doi.org/10.1016/j.jns.2015.03.015 0022-510X/© 2015 Elsevier B.V. All rights reserved.