Dataset Information

Compensatory role of the cortico-rubro-spinal tract in motor recovery after stroke.

ABSTRACT:

Objectives

Studies on nonhuman primates have demonstrated that the cortico-rubro-spinal system can compensate for damage to the pyramidal tract (PT). In humans, so-called alternate motor fibers (aMF), which may comprise the cortico-rubro-spinal tract, have been suggested to play a similar role in motor recovery after stroke. Using diffusion tensor imaging, we examined PT and aMF in the context of human motor recovery by relating their microstructural properties to functional outcome in chronic stroke patients.

Methods

PT and aMF were reconstructed based on their origins in primary motor, dorsal premotor, and supplementary motor cortices in 18 patients and 10 healthy controls. The patients' degree of motor recovery was assessed using the Wolf Motor Function Test (WMFT).

Results

Compared to controls, fractional anisotropy (FA) was lower along ipsilesional PT and aMF in chronic stroke patients, but clusters of higher FA were found bilaterally in aMF within the vicinity of the red nuclei. FA along ipsilesional PT and aMF and within the red nuclei correlated significantly with WMFT scores. Probabilistic connectivity of aMF originating from ipsilesional primary motor cortex was higher in patients, whereas the ipsilesional PT exhibited lower connectivity compared to controls.

Conclusions

The strong correlations observed between microstructural properties of bilateral red nuclei and the level of motor function in chronic stroke patients indicate possible remodeling during recovery. Our results shed light on the role of different corticofugal motor tracts, and highlight a compensatory function of the cortico-rubro-spinal system which may be used as a target in future restorative treatments.

SUBMITTER: Ruber T

PROVIDER: S-EPMC3413760 | biostudies-literature | 2012 Aug

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Compensatory role of the cortico-rubro-spinal tract in motor recovery after stroke.

Rüber Theodor T Schlaug Gottfried G Lindenberg Robert R

Neurology 20120725 6

<h4>Objectives</h4>Studies on nonhuman primates have demonstrated that the cortico-rubro-spinal system can compensate for damage to the pyramidal tract (PT). In humans, so-called alternate motor fibers (aMF), which may comprise the cortico-rubro-spinal tract, have been suggested to play a similar role in motor recovery after stroke. Using diffusion tensor imaging, we examined PT and aMF in the context of human motor recovery by relating their microstructural properties to functional outcome in c ...[more]

PMID: 22843266

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Dataset Information

Compensatory role of the cortico-rubro-spinal tract in motor recovery after stroke.

Objectives

Methods

Results

Conclusions

Publications

Compensatory role of the cortico-rubro-spinal tract in motor recovery after stroke.

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