Can stroke patients walk after complete lateral corticospinal tract injury of the affected hemisphere?

Abstract

The lateral corticospinal tract is the major motor pathway in humans. The role of this tract on walking, however, is uncertain. The development of di¡usion tensor tractography enables corticospinal tract status to be visualized at the subcortical level. In the present study, we undertook to demonstrate that some stroke patients can walk despite complete lateral corticospinal tract injury. Ten stroke patients who were able to walk with evidence of complete unilateral lateral corticospinal tract injury, as determined by clinical course, brain magnetic resonance imaging, and di¡usion tensor tractography, were recruited. We conclude that some stroke patients can walk despite complete lateral corticospinal tract injury of the a¡ected hemisphere. NeuroReport17:987^990

Noninvasive Neuromodulation in Poststroke Gait Disorders

“…17 The evolution of the corticospinal tract (CST) in mammals is associated with the acquisition of motor skills. Several studies show that people affected by stroke could walk even after extensive damage of the lateral CST, [18][19][20] although the upper-limb motor function remains severely 1 Scientific Institute Vita-Salute University San Raffaele, Milan, Italy impaired. 20,21 However, CST is considered essential for skilled gait by modulating the walking pattern in response to environmental influences.…”

“…Several studies show that people affected by stroke could walk even after extensive damage of the lateral CST, [18][19][20] although the upper-limb motor function remains severely 1 Scientific Institute Vita-Salute University San Raffaele, Milan, Italy impaired. 20,21 However, CST is considered essential for skilled gait by modulating the walking pattern in response to environmental influences. [19][20][21][22] Fine control of walking involves several brain regions, including the sensorimotor cortex, supplementary motor area (SMA), cerebellum, and brainstem.…”

“…20,21 However, CST is considered essential for skilled gait by modulating the walking pattern in response to environmental influences. [19][20][21][22] Fine control of walking involves several brain regions, including the sensorimotor cortex, supplementary motor area (SMA), cerebellum, and brainstem. 23 Several studies suggest that upper-limb brain activity is mainly lateralized over the contralateral sensorimotor regions during unilateral motor task in healthy individuals, with differences pointing to a less-lateralized activation related to aging or complexity of the motor task.…”

Functional Role of the Corticoreticular Pathway in Chronic Stroke Patients

“…[1][2][3][4][5] The descending motor pathways are classified according to the corticospinal tract (CST, pyramidal tract) and non-CST (extrapyramidal tract). 6,7 A number of studies have reported on stroke patients who were unable to perform fine motor activities of the hands after complete injury of the lateral CST; [8][9][10][11][12] in contrast, recent studies have demonstrated that stroke patients were able to walk even after complete injury of the lateral CST, suggesting that walking is not as strongly associated with the lateral CST as hand function. 3,9,[13][14][15] Greater involvement of non-CSTs in walking ability has been suggested.…”

“…6,7 A number of studies have reported on stroke patients who were unable to perform fine motor activities of the hands after complete injury of the lateral CST; [8][9][10][11][12] in contrast, recent studies have demonstrated that stroke patients were able to walk even after complete injury of the lateral CST, suggesting that walking is not as strongly associated with the lateral CST as hand function. 3,9,[13][14][15] Greater involvement of non-CSTs in walking ability has been suggested. 9,14,15 In particular, the corticoreticulospinal tract, consisting of the corticoreticular pathway (CRP) and the reticulospinal tract, is known to be an important neural tract for walking ability [14][15][16] because it mainly mediates proximal and axial muscles; consequently, it is known to have a major role in relation to walking ability.…”